how long ago was this? this is what happened to me in 2008. somebody disputed a $600 item i sold but even though my paypal account was "negative", and kept prompting me to authorize paypal to transfer funds from my bank every time i logged in, it never tried withdrawing from my bank account on its own. maybe in later stages of the dispute it will do that?
as for the OP. i was lucky to have an honest foriegn zero feedback ebay bidder. I sold a $1500 laptop and had to ship it to australia. his paypal acct and address was verified and was quick with communication so it relieved me a little bit. needless to say, i paid $300 to ship it there UPS with signature confirmation and insurance, just to cover my ass. I still ended up making about $400 from the deal because lenovo laptops are overpriced over there and the bidder was willing to pay the extra USD for it.