Credit Card Processing

I've finally made the move to upgrade the source files of my magazine back issues website to be more dynamic. Before, the pages used only HTML and CSS. All issues were hard coded into each web page. I would have to manually edit the HTML page in order to add a new issue. For the 2012 issues, the issue data is now being stored in a MySQL database. It's then displayed using PHP. I have an admin piece where I can login and enter the info for each new issue to store in the database. The upside to that is I can use any computer with an internet connection to add a new issue, rather than being tied to the computer storing the source data.
I use PayPal to handle all payment transactions. It makes things much easier. I don't have to worry about bounced checks, counterfeit money, invalid credit cards, etc. I am thinking of looking into alternative credit card processing services though. PayPal takes out a lot of fees for each transaction. It's not much, but it does add up over time. A seamless, no fee system where I don't have to do any manual processing would be great.
Credit card processing seems to be able to be done from anywhere. A salesman from Southwestern Advantage stopped last summer and convinced me to buy a set of kids reference books. I put the books on my credit card. The salesman didn't have any POS systems with him. He just called a number, gave them my credit card information, and the transaction was completed. I was kind of skeptical it was legitimate, but it was. Southwestern Advantage turned out to be a company that hires college kids who would like to run their own business for the summer. They go to another state and sell books all summer. The guy who stopped at my house was from Minnesota and had been selling books all over the valley. He mentioned names of people I actually knew. He was very friendly, but a real smooth talker. Before I knew it, I was signing a paper and buying the books, while wondering to myself, why am I buying these. lol. They were nice books, but expensive, although he somehow convinced me otherwise.