I did all my helo training in Fresno CA. Had a great time, fantastic scenery closeby - yosemite and kings canyon etc. As an earlier poster mentioned nice quiet airport with very friendly atc.
I trained at Mazzei flying service and can thouroughly recommend them.
www.flymfs.com
My only caveat is that the central california valley is apparantly prone to thule(sp?) fog that can last for weeks at that time of year - suggest you contact mfs for the low down on the weather there.
Have fun!