I'm replaying Honest Hearts and does anyone know where I can get a s*it ton of 45. ammo for the pistol and tommy gun? Or cases then I could make my own ammo.

Joshua Graham should have a good amount. Otherwise you can kill the White Legs that use the .45 SMG.

Joshua has alot of ammo on him or in his general area?

He has the ammo for sale, and there could be components for it in the boxes near the Reloading Bench.