I solved this in a bizarre way. I wrote a ruby script to parse an .obj file and spit out the C code to load the vertex/normal/textureCoords of a model. Then I paste that into a class I have for loading and rendering models.
It's working, but if I can figure out a parser for .obj dorectly in Obj c, that sure would make me happy.
Start with Collada. It's a verbose XML format, and supports (almost) the entire scene graph, including models, materials (and textures), vert weights (for skinning), animation, cameras, lights etc.. Fast becoming the industry standard so you'll find a lot more information on using it than you will with OBJ and 3DS files (which don't contain animation data anyway).