Bizresearcher has given you some excellent advice.

The first thing you need to do is write your business plan. The very first (of many) business plan I ever wrote was actually for a wedding chapel business. I took it to my local SBDC office and the counselor loved it and sent me off to banks he knew were favorable to start ups. The bank loan officers were truly impressed that I was so prepared and immediately sent it to the SBA rep for approval.

I was told most people walk into the bank asking for loans and don't even have a business plan in hand.

The business plan will force you to see every aspect of your idea in complete detail. You will know whether or not your idea is viable when you take the time to see it in black and white.

It's not as difficult as it looks. Mine only took 3 weeks from start to finish and included every required financial statement.

See below for step by step direction:
http://www.smallbusinessstartup.biz/plan/