If your dont do backups, or have the contacts on outlook and can be sync back,if you dont...you are SOL like the above post stated, what I want you to do right now is d/l PimBackup (freeware) start backing up your contacts. Lets just say this is a lesson learned and the hard way.
I cant remember if it will work after the contacts are gone, but if you copy your Pim.vol and open it up via "notepad" it will look like a mess, but you can put together some contact parts and make it out if you really need a certain number.
Pimbackup:
http://pocketpcfreewares.com/en/index.php?soft=1806