Hi Sharon.

Whatever options you may wish to consider, please don't forget to look at Paypal. They make it really simple.

We used them on a site which we developed and we found them far simpler than (and competitive with) the main stream banks.
We used them on Digital Recall - Worlds First Free Digital Signage Software.

Initially we started with a bank, but we "gave it away" after all the hoops that we faced with them. too hard!

Good luck!