tips for river fishing..

I need some tips for river fishing. I have this spot that i think myght hold some fish, what do you guys think? its a sand bar on the out sidecurve of the river leading down to about 8 feet on the other side. (very small river can cast all the way across if i want.) it has large bolters just below the sand bar in about 3 feet of water and a sunken tree just above the sand bar. about a mile up the river there is very shallow white water and about 1/4 mile below the sand bar theres another one. I know there are cahnnels and a few blues in the river and deffantly flatheads, I once saw my uncle catch a 43lbs flathead finger fishing (under the bolters mentiond above) witch is now hanging on his wall. so i need tips on how to fish it and what bait to use. it dosent matter what kind od cat i catch i just want to catch one. do i just plunk the bait right ount in the middle of the current? how would someone go about useing a bobber in the river? ive heard that benny roberts punch bait has cut fish in it so would that be a good bait to target all 3??? HELP!!! p.s i landed a 18 lb flat head at that place today on a bluegille rig useing hotdoge as bait. WOAH!!! but no other luck..