Writing a credit card widget from scratch?.. Can I? well yes, do I want to ? um, not really. I've dealt with 3 or 4 different merchant account providers and .. well lets just say they are not fond memories. They are all proprietary, use different terminology for the same things... ugh, I still have the dents in my desk that match my forehead.

About the only positive experience is a drop in widget for OSCommerce and Authorize.net , both the widget and Authorize.net work exactly as advertised.

For stuff like that.. or anything that is beyond my capabilities or patience, I outsource it on Scriptlance via that pretty banner in the upper left, I created that banner for them btw