Here is a very good archive of over 700 Windows TrueType fonts - all of them are free to download individually as ZIP files.
Note: Some of these fonts have restrictions on usage if you are going to use them commercially - so please read the text file that will be in the downloadable ZIP file.
http://www.downloadfreefonts.com/fontfiles/afonts.htm
This site has a bunch of FREE TypeType fonts
http://www.wcfonts.com/ (http://www.wcfonts.com/)
Over 13,000 free fonts (and over 31,000 commercial fonts) - at least that's what the web site says:
http://www.searchfreefonts.com/