At present there are four sources I am aware of outside the banking community. Soon there will be five. I know this because I have been working with the company who will soon be offering them since 2013.
No matter which source you use, you will need a business plan. It needs to be as complete as possible.
In the U.S. many people at least try for SBA loans.
If you have a good relationship with your local bank in reality it is the best place to start. At the end of the process at least you will know what you need to get a non-traditional business loan. Most banks can also lead you to the other four sources.