I blog about Virtual Server a lot (as you may have noticed), but I'm not alone. Megan Davis is a technical writer/author at Microsoft who especially focuses on Virtual Server & Virtual PC and is extremely active both internally within Microsoft answering employee questions on discussion groups and the like and externally via her blog and newsgroups. Rather than me regurgitate what Megan has recently blogged about which would hardly be fair (and she did beat me to it:-) ), here's some links which I think will be really useful to you if you're interested in knowing more about Virtual Server. These entries have all posted by Megan over the past few weeks.
Dealing with a VHD that grew too large is about how to compact your hard disksIncreasing the size of a VHD is a couple of ways to do exactly what it says in the titleHow Microsoft is using Virtual Server documents some really cool ways we're using VS to solve solutions internally.
There's lots more up there - have a browse through, I promise you won't be disappointed. Megan, you're a star :-) Keep up the fantastic work!!!