Blue Gill & Crappie
I find the Blue Gill Are best caught on a hook (small) ,bobber and worm. You can use a small piece of night crawler. In the spring and summer, blue gill are usualy found in shallow waters near or inside the weed line. They may be near the surface if there is a bug hatch going on. Other times they will be deeper. In the fall as the water gets colder they can be any where.
Crappie are a little harder to find. Early spring they come to shore areas to spawn or bed much like a blue gill. Most of the rest of the year the will be found suspended in deeper water, either in open water or near brush piles or deep structure.
In shallow water,they are caught easily on a fly rod with a wet or dry fly. In deeper water I have caught them on a small jig or a small Super Duper. I've even had them hit the Super Duper at night.
Other people may sugest other methods. all will probaply work. Hardest part is to locate the fish.