I tend to do lots of Ubuntu installs, and I'd like them to be up to date from the moment I do them, and not have to install a bazillion updates as soon as the install finishes. I'd also like to cache those packages somewhere on a machine on my LAN, so I don't re-download all the packages every time. How easy is this to achieve? Is there a guide somewhere to making this happen? Bonus points if I don't have to burn any CDs or use USB sticks!

Edit: I have noticed a lot of guides for PXE booting and would be tempted to set this up but every time I find one they seem to be old/outdated and broken. My home server runs 10.04 LTS.