paypal.co.uk is the british site equivellant of paypal.com.
if you follow the link www.paypal.co.uk/uk
it actually redirects to paypal.com. it's a very standard practise for people to buy all the domain names that pertain to their name because it stops people camping on their domains.
hence the reason that sites like microsoft own all the domains that have microsoft.toplevel
if the money is in your paypal account it is as good as yours...
I suggest that you wait a few days and transfer the money to your bank account...
there are several hooror stories of people thinking that they've recieved money from paypal, sending items, only to then find out that the person doesn't actually have the money, and the funds are returned to them, in the same way that a cheque might bounce...
ebay probably stopped the auction because it recieved a high bid from a country known for it's scam artist. (racial profiling FTW!!!).
the best thing you could do, (IMO), do not under any circumstances try to send the money back thorough paypal. if you send a few thousand dollars to return the money her sent you, then his gets returned you've atcually lost that money,
Paypal is not a bank nor a money escrow service! -they are not very helpfull either when people do scam you!
the best thing to do, as I said is wait a week, if the funds are still in your Paypal account and not returned,transfer the money to your bank acount and wait another week. (you'll have to pay a business chanrge to paypal for transfering a large amount since they'll see you as a business customer then. once you've transfered the funds wait another week to make sure that they are transfered and that they will not be returned.
assuming it's been two weeks, and the money is safely in your bank then go and talk to the bank to make sure that the funds have properly cleared. (usually banks will let you spend the money whilst it's still on promise from another bank, then if the funds don't clear they will just tell you you are overdrawn, and charge you for the problem.)
so if you've had the money a couple of weeks, it's out of your paypal accounts and in your bank. it's fully cleared, (which takes about 5-7 working days usually).
then I suggest that you bubble wrap th exbox and sen it to nigeria, and renew your faith in humanity...
if the funds suddenly disapear then you'll have neither lost nor gained nothing, and can easily relist the Xbox, compaining to Ebay about not having to pay the funds anymore.
p.s not every one who lives in nigeria is a technological criminal.