i usually end up checking out label sites like:
www.alternativetentacles.com
www.havocrex.com
www.cahrecords.com
www.profaneexistence.com
www.aversionline.com is a good online zine
www.contempl8.net good place to get political shirts/stickers/etc..
www.crimethinc.com - good source for "revolutionary" news
when i cant think of the name of a band, but know the song, or just want to check out some unknowns ill try
www.interpunk.com
and of course myspace is a good way to find local bands, i especially like the way you can search by band name, genre, country, state, etc.