Boards from a local lumberyard are a better choice of wood to start with. Easier to lay-out, dry wood, you can pick the right board yourself and MUCH cheaper than a stave. For beginners, I would highly recommend a board that you can get locally. I never buy staves, but only buy boards. I get my staves myself.
That being said, I'm convinced both Ebay and this message board can both offer you very nice wood. But placing a bid, waiting for the wood to arrive by mail, and then just hoping the wood will be dry enough, all take more time than buying a board.