Found an interesting online service today, called WhatTheFont?
Designed to help you identify a font whose name you don't know, it accepts a bitmap image of your mystery font for analysis, then suggests the closest possible match plus similar ones.
Armed with the name of your font, you can go google for something free, or click the link they provide to buy a commercial version. Neat!
I tried it out on a few known fonts I had laying around and it's uncanny. Just the kind of thing you don't know you need until you really need it.