I can't help you too much on this, other than to make the distinction between veneers and laminations. The veneers are very thin strips that are generally made from exotic woods, and are glued on the outside of the laminations. AFAIK, the veneers are purely cosmetic.
The laminations are thicker and do the work. There are not as many options for laminations as for veneers. Common options for laminations are maple, bamboo, osage orange, yew, and a few others. I don't know much about homemade bows, but I have seen or heard of homemade bows using many different types of wood for either self or laminated bows than I have seen offered by bowyers. Many bows only have laminations and no veneers.