Resurrecting a topic with some new information I found. I was about to go with Midwest Transaction Group per Bret's recommendation (their fees are very competitive--$5 per month, 1.69% to 2.89% plus .20 transaction fee), when I found another alternative.
If you have a need to be able to take credit card payments from your clients (not via a website, and not live in a store setting), I have another alternative besides setting up a credit card account: You can use your PayPal business account (which is free) to email a PayPal invoice to your client and get paid through PayPal with a credit card or PayPal balance.
The fees are as follows: No monthly fee! 2.9% plus $0.30 per transaction.
While 2.9% (and .30) are a bit on the high side, there are two bonuses that make it worth it (besides not having to pay the monthly fee).
1st bonus: If you get a PayPal debit card (also free), you can use it for purchases/payments from the money you receive and you get an immediate 1.5% cashback bonus. This lowers the effective fee to 1.448%, plus the .30 transaction fee.
2nd bonus: Any money you've received that sits in your PayPal account automatically earns money market rates (currently 4.69%)--try getting that with your checking account!
You can also download the transaction info into quickbooks.
It's working great for me. Let me know if you have any questions.

