Did you have Lookout mobile security installed? If so go to https://www.mylookout.com/ It can locate the phone down to about a 5-10ft area.
If you don't have it installed, it's well worth installing. It's free for Droid X and Droid 2 users.
You can try calling VZW and asking what they can do, but I don't think you will get far. Worth a shot though. Better do it before you battery dies tho.
I have never used it, but I'm wondering if the family locator option can be turned on for that line?
It would have to be activated by the handset.
I'm afraid unless you have somethign like my look out enabled with gps track your only hope is that if you call it you can find it. Or talk to vzw about putting a single trace on the phone so if it is used you know but highly doubt that would happen. Option 3 is that you have verizion disable it and if you have the lost/stolen replacement use it.