Take a couple of them down to your Golfsmith-type place or the best course near you. They (or the Pro) will be able to quickly determine if they're fakes.
There are thousands of counterfeits on eBay, especially wedges, and I've even come across a Seller who unbeknownst to him wound up with six dozen fake Pro V1s. Any novice golfer would likely not know the difference.
If any eBay golf club is "brand new" and the Seller has more than one for sale at substantially less than the going price, it's almost always fake. Esp if the Seller is overseas.
Before bidding, always ask the Seller if he can guarantee that the club is authentic. If he doesn't respond in a day or two, it's more often than not a bogus club.
When in doubt, ask the seller for the Serial #'s..if legit, he/she will be glad to give you them, then contact the manufacture and validate them. I only buy from sellers in the USA, and highly rated sellers, i.e. 3ballsgolf, globalgolf, ect.