Choosing the right font or fonts for your business card is increasing difficult.  Here is a comprehensive article on how to choose a typeface from Smashing Magazine http://bit.ly/t6uHgM

Once you have chosen a font you can find it at a number of online font websites.

Try these three for starters:

Font shop http://www.fontshop.com/

My Fonts http://new.myfonts.com/

Fonts 101 http://www.fonts101.com/