Guitar Tab Universe - http://www.guitartabs.cc/ Artist and song search along with an artist directory to find guitar and bass tabs
Guitar Tab! - http://www.guitaretab.com/ A large list of guitar tabs organized by artist in a browsable directory.
Harmony Central - http://www.harmony-central.com/Guitar/tab.html A guide and search engine for the OLGA, links to other tab sites and some commercial tab vendors are also listed.
