I need to be able to translate my 3D geometry to 2D space. I had some sample code on how OpenGL can do this and I can do it in DirectX but I don't have a clue as to how to do it on the iPhone. Does anyone have any experience with this or know of any links that they could share? Thanks again.

Edit: I could probably implement a picking algorithm, which involves a picking ray based off of the view port and where the screen was touched and then performing a simple collision test on that ray with the 3D objects in the scene but what I was hoping to find, more specifically, is the 2D world space coordinates of my 3D objects at a center point for example.

Grab the source to whichever of gluProject and gluUnProject it is you want (I can't tell from your explanation) from the Mesa Git repository.