There was a spotting scope comparison recently in Bird Watcher's Digest, where they rated scopes at various price ranges. Check out
http://www.birdwatchersdigest.com/site/index.aspx and do some digging.
They also have an article on digiscoping, which I have found to be less than possible with the camera that I use.
My experience with spotting scopes is that they are disappointing unless you buy at least a decent mid-range one, and the top end ones are MUCH nicer in terms of clarity and lack of eyestrain. Monitoring a peregrine eyrie with a Swarovski is a whole lot easier than trying it with a Bushnell. If I had $3K lying around I know I would invest in a good one. I also suggest considering the armoring and delicacy of the scopes you choose, and invest in a case for it and a good tripod as well. I would NOT buy one without having looked through it and used it. I did that with a scope from Cabelas for my dad and was sorely disappointed.
Many of the top end scopes have digiscoping adaptors available.