entomology

I'm hoping someone can point me to a site that has photo's of the
various insects and the representitive fly. I fish the Catskill area
primarily but am hoping to explore Penns' and North Carolina mtns. I'm
somewhat adept with the cast as well as sizing the fly but for the life
of me I can't get the hang of insect identification. I do all my
fishing with other novices so they aren't too much help either! Thanks
in advance. Bill in Virginia