Monty-
Please do yourself a favor and go and talk with the owner of the proshop at your local bowling center. The used balls you are seeing on Ebay for cheap are not what you want if you are learning to hook the ball. Go and talk with the owner and tell him what you are looking for. Chances are he has some used balls for sale that would fit your need better than taking your chances on Ebay. Even if you get a ball for cheap on Ebay you will still have to have it plugged and redrilled anyway.
Please don't take this as a slam, it is not meant that way at all, but the guy in the proshop is your best bet for your first ball.
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Whether you think you can, or whether you think you can't... you're probably right.