You'll find a few other options here...

http://www.google.com/Top/Business/T...ers/Providers/
http://dmoz.org/Business/Telecommuni...ers/Providers/

The Best business by phone Expert and resource...

Excellent Free Sales Tips by signing up...

Art Sobczak's
http://www.businessbyphone.com/
(there seems to be a few html problems on the home page but I'm sure it will be fixed soon)

Phil