[initial thought follows!]
If the auction is over and the winner reneges, the seller can only offer it to the second highest bidder; the second highest bidder is not obligated to accept the terms.
[follow-up thought...and probably what you're *really* referring to!]
Now, if you're saying that *before* the auction was over, you had been outbid...so *then* you went looking for a similar item and bid on it elsewhere...and then the top bidder in the first auction retracted his bid, making you the high bidder in the end?!? (I think I'm following your train of thought here)
Anyway, to respond to that scenario...yes, you'd be obligated to fufill all transactions you won.
Your options would be:
1) to retract your bid from the first auction, so that you could go bidding elsewhere without fear of winning two identical items,
2) you could wait until the first auction was over before searching out other auctions,
3) you could go ahead and buy both and sell one on eBay
I think it is usually pretty rare for folks to retract their bids...afterall, most would fear that this would look bad on their feedback sheet; I have to agree with the thought that if you had two retracted bids on the same auction, well, I would be suspicious that they were either trying to push up your bid (a no-no according to eBay) or trying to figure out what your max proxy bid was. I think I would be inclined to report the activity to eBay as it just doesn't sound right.
Happy sniping!
WarriorNun
"If you can't be a good example, then you'll just have to be a horrible warning"