Do bass hang on main lake points at the mouths of creeks during the summer? And also where do you look for ledges in a lake? Lastly what baits? Crankbait,carolina rig,football jig or drop shot?

Bass will hang out on main lake points throughout the year using different depths, structure on the point, cover, etc. 

Mouths of creeks, where they meet the main river channel or converge with another creek are prime spots for feeding, especially if there is some current.

Ledges can be found almost anywhere in a man made lake, the only way to find them is either with a topo map and your electronics or by looking at the exposed shoreline.  Ledges are often found along bluffs that extend into the water.

What baits to use in any situation is a determination that can only be made on the water as you need to take into consideration factors such as water depth, color, light penetration, etc.  Then you need to consider the fish; what depth are they holding, close to cover or structure, activity level, season etc.