If i give out my credit card # online, they always say that my billing address MUST match the one on my credit card statement, the question im asking is, if I enter a address that is not my credit card statement address, can they find out? thanks

yes.... why else would they ask for it if it could not be verified?

Absolutely. Matching your address on your credit card statement to the address that you provide to the online company is a way that online retailers combat fraud. I faced this situation when I was using a company credit card to order some supplies for my office. I accidentally entered my home address as the billing address (hadn't had my coffee yet!) and the charge was rejected. Then it was a total hassle to get that corrected and place the order. I had to convince them that it was an honest mistake and give them the correct billing address as well as a bunch of other info to prove I was authorized to use the card.