Western Union. NEVER, EVER pay for anything off of eBay using Western Union. Its the first sign that something is funky. If the seller won't take a legitimate, tracable, recoverable method of payment, run like hell.
The internet is the biggest thing to happen in my lifetime, and eBay is the biggest thing to happen to the internet. I've done thousands and thousands of transactions on eBay. My music gear, 99% of my dive gear, fishing, camping, electronics, countless cameras, computers, fine silver, china, rare books, expedition wear, shoes, furniture, tickets, CD's, theatrical lighting, blah, blah, blah. too much to name here.
To remain eBay ignorant today is to your sad discredit. Treasures await you. However, this one point is not negotiable.
Never pay via Western Union. Never, ever, ever.
Ken