7250 locked

Hi,i have a 7250 and it appears to be locked....to be honest i found it..but could not trace the owner as like i siad it was locked......so...is anybody willing to have a go at sorting it out for me? i have been looking on the forums and i'm baffled....had a go with a 3310 once but really messed it up :lol:

thanks in advance

Note:
when you type in a number, it say's Emergency calls only, so i typed in 999 which it did not recognise, so i type in 911, that it recognised so i am assuming it's from USA