Some sites to check out: http://www.3darttopart.com/ http://www.toybuilders.com/ How expensive the prototyping process will be depends on a number of factors like what material the prototype will be made from, whether you're getting just the object iself or if you're also getting an accompanying master mold, and how much labour is required to clean up a submitted 3D file. You can keep costs substantially down by opting to have prototypes made in less durable materials (instead of a variety of plastics/metals etc), doing the majority of the 3D file clean-up yourself, and doing your own master molds if you have the intent to produce multiples. I'm interested in doing some rapid prototyping myself eventually, but I just haven't created anything I feel is special enough to warrant it yet.