wildlifedepartment.com has stocking figures for the last few years. That may give you some info. You do have to dig a bit to find it. Also call the area game warden. Good Luck & Tight Lines
Keep plugging away. This is not the easiest time of the year to locate fish. They could be shallow in the grass, deep on points or hanging anywhere between.
All of the above plus: Watch a lot of YouTube. Plenty of good instruction is available on line. Observe. Spend time watching others at the launch ramps, docks, marinas.
My friend Rocky Thomas is a guide for all the lakes in your area. He is laid back and will teach you what you want and you will have a good time. https://www.facebook.com/thomasguideservice 918.837.0490