My personal favorite free font website is www.dafont.com . They have a lot of categories, and even have a neat sample tool so you can see your text in the font before downloading!

dafont.com - really great site I've used for ages, sometimes limited selection.

betterfonts.com - HUGE collection, great interface, hard to sort thru so many and you have to look at alot of crappy fonts.

larabiefonts.com - this used to be my primary site, they are all custom made fonts, but they started to make most of the new fonts not free, but cool to check out every now and then for some original typography.

creamundo.com - pretty much the same at betterfonts.com, but more unorganized, nice to look as a last resort.

There are tons more resources, but most of them end up being the same selection, with tons of ads, and crappy search.