Logging Your Servers

We have quite a large number of servers now but I'm now finding it harder and harder to keep log of the number of details for it. How do the bigger guys keep control on this? Ie: Keeping logs of the serial/product keys of each part in the server, where they were ordered from, what date was it ordered etc?

My collection of growing motherboard, ram, processor boxes (which all store the serials of the products on) are now slowly taking over the office even when flat packed. I normally just write on each of the boxes where the product was ordered from, date of order and server name. While this is all well and good.. 50 servers later it can be a bugger to find the serial of that dedi mobo without going to the DC.

I tried my efforts at a simple Access database but I kept finding I spent more and more time typing in complex keycodes into the DB and just gave up. When this has been done it sounds nice and easy but then I hit another stump.

Ontop of logging a new servers details, how do you log which server is available to be sold, who its been sold too? ATM we have a VPN shared spreadsheet with all the details in (praying that the other employees will actually update it) but Im not sure if it will stand up when it hits 100+ servers rather than the 50+ atm.