Well a lot of this depends on what you're wanting to do with your physics and what kind of game you're making. Is it tile-based or otherwise? What have you tried that you weren't satisfied with? Are you sure that your detection works?
It's 3D and i'm using lwjgl (OpenGL) and I only want to do really basic stuff. I had an algorithm that worked but I couldn't detect where I walked into the cube. The algorithm was like on collision x -= x - sizeX (same with z), but since I cant detect what axis i'm hitting then cube on then it brings me to the same spot.