X181

Hello i will migrate an AD (based on 2k-server) to an AD (based on 2k3-server). the 2k3-servers build a new indipendent AD (this has several reasons...). same thing with exchange (from 2k to 2k3). the domain includes about 50 Workstations and new 4 Servers. a search tools tho do the following work secure, fast and if possible cheap my questions: - how can i migrate the user-accounts ( profiles, pws, exchange accounts, etc)? - how can i change the nt domain of the workstations? - how can i change the the mapi profiles of the users (new exchange server!)? sry about my english.... and thx in advance X181