Second Hand Songs is a database of songs, composers, original and cover performers. It's not totally comprehensive yet, but can be useful. For a more 'official' resource, there are the search pages at BMI and ASCAP.
Posted by M.Ace at 03:03 PM, February 06, 2005.There's also "The Covers Project" to look through:
Been around for a while - looks like they're updating the site this month...
Posted by Dean at 04:59 PM, February 06, 2005.