Hey Sliderman,
Paypal is THE MOST TRUSTED payment gateway on the internet. To make a payment, someone would only have to sign on to their paypal account and click "Send Money". After that, they simply type in YOUR email address and the amount of money they want to send you (with an option description of what they are paying for - just for record keeping). Their money is sent instantly to your account then. You can then use money in your account to buy other things online via paypal or you can transfer money (no charge) directly to your personal bank account. PayPal is very flexible that way and thus my first choice when it comes to my money online. Google is coming out with something similar but right the standard that everyone uses is PayPal. I hope this helps and let me know if you have any other questions.
All the best,
Chad