When first-time entrepreneur Philip Vaughn recently began searching for start-up capital, he traveled down two conventional paths.

Mr. Vaughn, co-founder of travel-review aggregator Raveable.com in Kirkland, Wash., says he wasn't interested in forking over a large chunk of equity to venture capitalists or committing to ambitious investment-return expectations. He also considered a loan, but knew that banks had made it onerous for young companies like his to obtain debt financing.

"We're...