Basic data structures for a 3D engine...

Hello I am in the design step of my 3D engine, I want to use DX8, but I am having some troubles to setup my data structures, like vertex, vector, matrix, camera, etc. My trouble is, wich will be the better method to declare my data structures to take full advantage of the DX8 features, for example, I know that DX8 utility lib has a lot of good math routines, but I want to implement my engine in C++ to support operators overload, so as you can see I am a little confe . Thanks in advance! Oscar