So i am watching the Apple Network Accounts video and my question is this what if there is already a profile on the mac and you want to put that mac on a domain do you have to create a new profile or will the profile transfer over to the network that you put it on?
Thank you for writing in. When you add your Mac to the domain, you will be able to login with domain accounts. Those accounts are separate from the local OS X user database, so they will get all new (empty) profiles.
The official answer that there is no way to merge the profiles. You would then need to copy all of your data over from your old profile into the new one. Some preferences (like wallpaper) will not copy over, but your documents and other files will.
However, Apple does have a round-about way that you can merge the two accounts. I usually use the method listed above because it is easy, but if you want to preserve things like 3rd party application prefences, you can follow the steps in this article to try and merge them.
Hope that helps,