I'm afraid you are not alone ... you have been scammed. Try to cancell your payment through your credit card company and also possibly your card.

Limewire basic if Free and you can update to pro at any time if you wish but it will cost you $18,88US see http://www.limewire.com/english/content/download.shtml

If you search the forums ... above right you will find a lot of posts conaining the word "scam"