I did follow that advice yesterday akistdm, but now I have an order today and it is still showing that my credit card processor is the referrer. I just added the domain in the referral exclusion list. I don't have to do anything else, right? Maybe I'll go and check to make sure I did it right.
Edit: I did add it in there… but I added paypal.com and beanstream.com. Do I have to add www.beanstream.com and www.paypal.com? Perhaps that is the problem?
You added right, without www. You must use universal analytics to work.
Ok, I'll check if I have universal analytics. I thought I did since the Analytics script on the site is named correctly. But maybe there is something else I'm missing.
Editing to add that on my site I appear to be using the “the Universal Analytics tracking code for this property”. It's the same script on my pages as what Google Analytics wants under “Admin” → “Tracking info” → “tracking code”. The tracking ID starts with a UA and the status is “receiving data”.
New edit! I just checked an order from today and it appears to have worked! So maybe it just took time to filter through? Not sure. Anyway, it showed Google search as the referrer this time on a credit card order so all is good.
I did add in the www. domains as well under my exclusions list, so maybe that is what fixed it too. Can't be sure.
Thanks so much akistdm! I think this is good to go now!
Nice to hear that i helped!
Have a nice day! 
I have just implemented this. Will be curious to see the results. Thanks for sharing ths info!