I think this is all done through your bank. Typically there will be a fee...I don't know if its a monthly fee or a fee for each transaction or maybe even both. You many also need to purchase or rent the equipment as well. For shows a hand held wireless card scanner would be best. These are fairly new and I have seen them in the shows once or twice up in Canada...as well as being used by various fast food places which provide frequent delivery (ie pizza places).
If you don't already have one, banks may also require you to have a business license and be registered for Federal and state/province so you can collect appropriate taxes. For small vendors...it isn't always necessary to collect and pay taxes (basically you have to send the appropriate amount of taxes based on your total sales taken in per year. Otherwise, if you end up getting audited, could be in trouble for not sending these sales taxes, not to mention if you don't claim income from reptile sales on your yearly taxes). In Canada there is a minimum amount of money you are allowed from sales before you need to charge sales tax and send that to the government.
IF you are already set up as a business and send taxes etc then all this you will be familiar with already and its just a matter of you talking with your bank about setting up for Visa/American Express transactions with a portable scanner/card reader. There may be a 'three in one' package or already included...depending on the bank and options you take...which will include two or more major credit cards (ie Visa, American Express etc) and debit cards.
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PHLdyPayne
Forum Princess