Well, you wouldn't want to build a network and set up a server completely with NewEgg. However, going straight to the source such as Dell and HP you can't really go wrong. The key is getting a 3 year 24/7 five days a week warranty.
Did I say get a 3 year 24/7 five days a week warranty? The main point is that you get a 3 YEAR 24/7 FIVE DAYS A WEEK ONSITE WARRANTY. You can get an added extention for next to nothing. I don't care what anyone tells you on this board or anywhere, HP's support is the best ANYWHERE. And, anytime you have ANY problem with your server, you can call them at 4PM, and the part will arrive by 10AM the next day, free shipping and free part.
And, if you ask for a tech, you will have one out out the next day.
I had a major problem with my server for which I was out of warranty. The support tech told me I was out of warranty, but it was an easy fix so he put a bandaid on the problem. He then told me to call back the next day to get an extension, but I had to tell HP my system was perfect (which it was not). I called, got the extension for $155, and HP then spent at least $1,000 in parts and tech labor AT MY OFFICE. Two techs on three different occasions. The last tech actually gave me his home phone, his cell phone and his email. He lived twenty mintues away. He emailed me everyday to check on things. It crashed again; he came out, couldn't figure it out, and said, "I can fix this." But, I need to take it home to my bench. He took it home and brought it back in a day completely fixed. HP sent me a brand new mother board, two new RAID controllers, two hard drives, all cables and other minor stuff.
The key with any support person you hire is that they teach you what they are doing as they go. And, don't let them give you that job security crap. If they won't show you what they are doing like, "This is your DNS and it is the problem -- and you need to do this to your Active Directory, then tell them to go elsewhere." In my opinion, if they convinced you to go with 2008, they did you a disservice as Small Business Server would have been a better way to go. But, that is My Humble Opinion.
Think about it. Do you tell your patients you can't teach them how to maintain their cholesterol or blood sugars so you can see them back more often? No, you teach them so they can maintain their own health.
You have a hell of a server with a great OS (again I prefer SBS, because it is much easier to manage with many more tools for free to use with small businesses -- if you ever need to change, I would seriously consider doing that.)
Here is something I would SERIOUSLY consider for you or anyone. Use your personal PC, definitely a workstation and not a notebook, but you could use a notebook. Make sure it has a dual-core processor and at least 2GBs of RAM, preferably three. Now go to
http://www.vmware.com/products/server/ and download Virtual Machine Server edition for FREE. Install it on that machine. Whether you use Virtual Machine from VMWare or Virtual Machine from Microsoft, it is VERY, VERY cool. Once you install it -- very simple -- you install your Microsoft Windows 2008 Server onto it. With Virtual Machine, it is just that. You will have 2008 as a separate OS which will have no impact whatsoever on your actual machine. Once installed, you click on VMWare and up comes a list of your virtual OS, click on Windows 2008 Server, and your computer is running 2008 on its own little part of your hard drive utilizing as much RAM as you want. You can play around with it as much as your want -- install programs, uninstall, delete users, add users, change active directory anything, and it will not affect your computer or XP Pro. It's basically an entirely different computer. You can simply go back to square one on it at anytime. That is the best way to learn. The only issue will be activation. And you can also install Vista, 2000, XP Pro or as many OSs as you want and open them at any time. So, if you wanted to run AC on Vista to see if it were compatible, you could do it in Virtual Machine rather than installing Vista on a whole different machine.
If you need any help with it, let me know, but the site above will walk you through it.