What do I need to know about moving my Lightroom files?

I just ordered a Windows Home Server to give myself a more expandable storage environment. First on my list will be my digital pictures. I intend to make a copy first rather than moving anything. Once I do, how do I make LR see the new files as the library so that I can eventually repurpose the disk the images are currently on?

I'm not a LR expert so take my advice with a pinch of salt.
However, I think this is fairly simple. Obviously, LR doesn't know what happens outside of its environment. So if you change the file location, you have to "tell" LR. I personnally know 2 options, there may be more or better ones.

One option is to move the folders from within LR through the left pannel in "Library". Simply drag & drop your folders from your current volume to your WHS. It takes a while, but at least LR doesn't lose track of your files.

The second option is to move your files via Windows Explorer, and then update the file locations within LR. On the same left pannel, you will get question marks next to your folders after having moved them to your WHS. Right click on each folder, select "update location" and choose the new one.

In both cases, I recommend you to try with a few images which you don't care about, and once you're confident, roll out with the rest of your library.

Good luck

Are you moving the pictures or just the Lightroom library and thumbnails?

You can move the pictures outside of LR environment, but you have to update its location in Lightroom by right click on the folder and go to Update Folder Location

i just did this yesterday and used the Update Folder Location option. It worked flawlessly. I used teracopy to move the files and just updated location.. easy peasy.