for starters, i'd try calling your own phone first and see if anyone picked it up. it's a Telus phone, so cross your fingers who ever has it is smart enough to know they won't be able to reuse or sell it off (assuming it's the cdma version).
if that doesn't work, inform telus so they don't rack up long distance charges or whatever using your phone. might as well ask the telus rep what they can offer you as well, though it will be close to what CRS has mentioned. unfortunately,
you losing your phone doesn't void the original contract (unless it's expired).