You were scammed
. Try to get your money back by contacting your bank/cc company. They should have a fraud dept. that can help you out. Then try to contact the site you bought LW from and demand your money back. You should also cancel the account you used to pay with because (as you are finding out) they will keep tacking on extra charges.
Here are some threads that might help:
Membership? - **WARNING ** BEWARE** - Download p2p Clients ONLY Thru Official Sites get your $$$ BACK!!!(music members) List of Scam Sites
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http://www.limewire.com/english/content/download.shtml