Microsoft Office 2007 license self-audit?

I've been given the task of getting the company I work for into compliance. I currently have 71 users with Office 2007 installed:

35 users on key A 9 users on key B 27 users on key C

Here is my question. It is very likely that someone has purchased 35 licenses for key A, but how do I check? Is there a tool or website that I can enter my MS Office key into and it will tell me it was for x number of installs?

My plan is to gather this information and then buy the number of licenses we need. Can I "add" licenses to the keys we currently have so I don't have to reinstall/change and keys?

...Or of course if you can think of a better way to go about doing this then please let me know. Thanks.

Check if you have volume licensing (you can tell by looking at the install media) then it is possible someone has purchase 35 licenses for 1 key. I doubt you have retail because it will only allow you to activate it three times before you have to call. Of course it's possible someone sat through the phone activation for the other licenses but that is unlikely since there is probably some upper limit on phone activations. I know for older copies of Office 03 the automated system stopped working and I had to actually talk to a MS rep.

Are you certain they all have the same three keys? We had a bunch of retail versions before migrating to a volume license version and they all came with the computers when we purchased them from Dell. Here is the volume license site. You will need to get your companies sign in information to access your keys. However if you don't have a volume licensed copy, you cannot add licenses to a retail key you will have to purchase a volume license key and disk, the volume license keys do not work with retail version. I know this may not be the answer you are looking for but I have been dealing with getting my company SOX compliant since last year it can be quite a PITA. In my case we bought a volume license copy of office and we had to go and reinstall it on all the existing PC's.

If you want to read up on licensing terms for the different versions of Office you can do it here I found this useful when getting my company compliant. You might also want to follow these instructions just to see if the other copies are actually activated and not just installed.