There is indeed an abundance. If you google the search term "anti Bush songs" you will find such glories as:

Anti-war, anti-Bush and pro-peace songs at:
http://onegoodmove.org/1gm/1gmarchive/000628.html

A huge list of pop and folkpop anti-Bush protest songs at:
http://www.benfrank.net/nuke/Free_Peace_mp3s.html

http://whistleass.typepad.com/boot_george_in_2004/1_antibush_musicfor_fun/

And the ultimate George Dubya Bush Song Book at:
http://servercc.oakton.edu/~billtong/bnsp/bushsong.htm

also check out less well known bands like Burgess Shale, Austin Texas' Happytones, and Thought Travler, which have none too complimentary songs about Bush.

And pages and pages more. These are just a sample. The anti-Bush song industry is steamin', brother.