Lots of good info on the forum here.
Kern River Fly Fishing Forum - Index
Guy Jeans owns the flyshop in Kernville and guides trips into the GTW. He's the Admin on the forum "flyguy". If you join and do some searching you can get some good info. You can ask also but some on there get a little weird giving out info to newbies and strangers. Worried about bait fishers who don't practice catch and release.