Basic LW is free The only official site for downloading either Pro or Basic is Lime Wire » Official Website & Free Download, BitTorrent «.
The download page looks like this (which also shows you Pro's current prices): Lime Wire » Download LimeWire

Who did you pay for LW Basic? If you've only just bought it, contact your bank/CC company & let them know - they may be able to stop your payment or get you a refund. Check out the links below for more info.
Membership? - **BEWARE** - Download p2p Clients ONLY Thru Official Sites (click on link)

get your $$$ BACK!!! (music members)

If you bought Basic from a scam site, who knows whether you even ended up with a clean version of LW. My advice would be to trash what you have & then download a free Basic LW from the official site. Then post back if you're still having problems with playing files