Business methods may be patented. Priceline’s business model is a good example. However, it will have to be truly revolutionary to be protectable. If you are serious about it, start raising money. You will need at least $2000 to get a preliminary opinion from a patent attorney on (a) whether the idea is protectable, (b) whether someone beat you to it. If it looks promising, figure $5000 for a full patent search, then depending on the complexity, at least another $5000. Those costs can double or triple if you seek out a major-market (NY, LA) patent lawyer, or increase by several orders of magnitude if there are any difficult issues in your filing.
Good luck. I burned a lot of cash chasing a patent a couple of years ago. It was no fun. But if I would have had my idea 18 months earlier, and won the race to the patent office, I would be retired right now.