There are not many if any builders who owner finance. you should find a buyer broker who is well experienced in new homes who can help you through the new contraction process. There are loans such as construction to perm that funds the lot, building and then converts to a conventional loan once building is done.
A builder depends on a constant cash flow in order to keep construction going. Financing a home would be almost the same as leasing it ... small amounts of money per month after spending hundreds of thousands to construct the place. It makes no sense.
I don't know of many builders who does owner financing. Builders do have partnerships or in-house financing companies. The best thing to do is consult with a real estate agent and get a pre-approval to see if you qualify for a loan before you start looking.