[oomkiller]

I would work on a relationship with a bank, and get a merchant account. There are many providers that offer low enough rates for a startup. One that I heard of was Merchant Plus. Just get someone that supports authorize.net and you can't go wrong. This might take a little time, so I would recommend using Paypal AND Amazon payments WHILE you're getting this setup, since they seem to be easier to implement. I WOULD NOT however start with these initially, and not put any effort into a merchant account. You WILL need a merchant account eventually (if you're successful), so you need to already be working on it.