On a more useful note, I'm pretty sure there isn't a list and if there was it would have to be a list of paypal's members which might be in breach the data protection act (on which subject I am extremely unknowledgable).
yes quite a few sites use PayPal. I have also found when payment was required using Access (and I don't have a card) the business concerned were happy to take PayPal as will most reputable places.