True type fonts are very easy to come by, and large amounts of them are typically included in packages like Microsoft Word and Word Perfect. Getting Word Perfect is an easy way to get an enormous amount of fonts (and if you're really cheap, you could buy a legacy version of Word Perfect for windows. The fonts on the CD are readable.)
Luc Devroye's webpage has links to several sites with free fonts available. What's unique about these fonts is that a lot of them are really free, they are not ``warez fonts''.
There are several web sites offering freely available downloadable fonts. For example, the freeware connection has links to a number of archives.
Several foundries sell TrueType fonts. However, most of them are quite expensive, and for the same money, you'd be better of with Type 1 fonts. I'll discuss these more in the Type 1 fonts section. The one place that does do sell TrueType fonts at low prices is buyfonts. Please read the section on ethics before you buy cheap fonts.
Many foundries ship fonts with Windows and Mac users in mind. This can sometimes pose a problem. Typically, the ``Windows fonts'' are fairly easy to handle, because they are packed in a zip file. The only work to be done is converting the pfm file to and afm file (using pfm2afm).
Macintosh fonts are more problematic, because they are typically made available in .sit.bin format -- stuffit archives. Unfortunately, there is no tool for Linux that can unpack stuffit archives created with the newer version of stuffit. The only way to do it is run Executor (Mac emulator), or try running stuffit in dosemu or Wine. Once the sit.bin file is unpacked, the Macintosh files can be converted using t1unmac which comes with the t1utils package.
Unfortunately, some vendors only ship Type 1 fonts in Macintosh format (stuffit archives). However, according to font expert Luc Devroye, all major foundries make Type 1 fonts available for Mac and Windows.
ctan have a number of good fonts, many of which are free. Most of these are in Metafont format, though some are also Type 1 fonts. Also, see Bluesky who have made available Type 1 versions of the computer modern fonts. (The computer modern fonts are of excellent quality -- to purchase anything of comparable quality and completeness will cost you around $500-. They are comparable to the premium fonts.)
Luc Devroye's webpage has links to several sites with free fonts available. What's unique about these fonts is that a lot of them are really free, they are not ``warez fonts''.
URW have released the standard PostScript fonts resident in most printers to the public domain. These fonts are quite good.
The Walnut Creek Archive has several freely available fonts, and shareware fonts. Some of these are obvious ripoffs (and not very good ones). If a font doesn't come with some kind of license, chances are it's a ripoff. Also Winsite have several Type 1 fonts (in the fonts/atm subsection of their windows 3.x software). Unfortunately, several of these have afm files which have mistakes and are missing all kerning pairs (you can fix the afms by editing the "FontName" section of the afm files. It should match the fontname given in the font shape file. Of course, adding kerning pairs is a topic beyond the scope of this document.)
Luc Devroye's webpage includes several free fonts he designed, as well as a lot of links, and fascinating discussion on the topic of typography. This site is a ``must-visit''. There are also several links to many foundries.
So you're wondering -- why do some fonts cost a lot and others are cheap? These fonts are the ``standard PostScript fonts'' resident in most PostScript printers. Also the famous Why should I buy the more expensive ones? My take on it is that for a casual user, the value fonts (such as those on the Bitstream CD) are just fine. However, if you're using the fonts for ``real work'', or you're just a hard core font junkie, then the better quality fonts are a must-have -- and most of the quality fonts are either free (for example, Computer Modern), or they are upmarket commercial fonts.
The advantage of the cheaper fonts is self evident -- they are cheaper. The quality fonts also have their advantages though.
Ethical issues: The cheaper fonts are almost always ripoffs. Type design takes a long time and and experienced designer. Fonts that are sold for less than $1-per font were almost certainly not designed by the vendor. CDs with insane quantities of fonts on the are almost always ripoffs (the possible exceptions being collections from major foundries that cost thousands of dollars). Usually, the ripoffs lack the quality of fonts from respectable founries.
Completeness: The higher quality fonts (notably from Adobe) come in several variants, with some nice supplements to provide the user with a more complete font family. There are often bold, italic, and demibold variants, swash capitals, small caps, old style figures, and extra ligatures to supplement the font. More recently, Adobe have a multiple master technology which gives the user (almost) infinite variation within one font family.
Quality: A lot of the freely available fonts or the cheap ripoffs lack fairly essential features such as kerning pairs and decent ligatures. They are basically cheap copies. In contrast, reputable designers take a lot of trouble to study the original design, and rework it to the best of their ability.
Authenticity: The person who designed Adobe Garamond (Robert Slimbach) actually studied the original designs of Claude Garamond. In fact reputable foundries always carefully research their designs, rather than just swiping something off the net, and modifying it with Fontographer.
An excellent place to go for a CD packed with several Type 1 fonts of reasonable quality is Bitstream. Bitstreams more noted products include their 250 font CD and their 500 font CD (the latter goes for $50- at the time of writing). These are fairly good quality fonts, and are a fairly good starting point for the casual user. The fonts used in Corel's products are (mostly) licensed from bitstream.
Matchfonts offer more modestly priced fonts -- they are distributed in ``packs'' of about 8 fonts for $30. This includes some nice calligraphic fonts. All fonts seem to be offered in a usable format (the windows ATM fonts come in a .exe file. Don't let the extension fool you -- it's just a zip archive). These are not ripoffs as far as I can tell.
EFF sell TrueType fonts for $2- per hit. They also have ``professional range'' PostScript and TrueType fonts for $16- per typeface.
Adobe have several high quality, fonts available at Adobe's type website. Some of these are expensive, but they have several more affordable bundles -- see Adobe Type Collections. Adobe have some of the most complete font families on the market, for example, Garamond, Caslon, and their multiple masters (Myriad and Minion, used on their website are among the nicer of their multiple masters.)
Berthold Types Limited is a major foundry, who offer several quality fonts. Some of them are resold through Adobe, all are directly available from Berthold. Same price ballpark as Adobe.
ITC develop several quality fonts (including some of the ones Corel ships with their products) at http://www.itcfonts.com. They offer family packages for about $100-180 US. Their fonts, come in both Type 1 and TrueType format. It's better to choose the ``Windows'' package, because Mac formats are difficult to handle on Linux.
Linotype are a well known foundry who offer fonts by legendary designers including Herman Zapf. (yep, the guy ``Zapf Chancery'' is named after. He also designed Palatino.)
Monotype develop most of the fonts shipped with Microsoft products. One of the older and well respected foundries.
Tiro Typeworks sell good quality, if somewhat expensive typefaces. Their typefaces are very complete, for example, they include complete sets of ligatures, and smallcaps, titling fonts, etc. UNIX is listed as one of the OS options -- which is a welcome surprise after seeing the words ``Windows or Mac'' too many times.
For links to a bunch of other foundries, see Luc Devroye's page