It's pretty easy to script domain account creating, but I haven't seen a script for Exchange account creation yet.
A script for account creation can be as simple as something that uses 'net user' commands. Here's one I use, with comments:
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# Script is named 'newuser.cmd'.
# This file takes up to four input parameters:
# username, password, full name, and group name
# the first entry adds a user to the domain
net users %1 %2 /add /fullname:%3 /domain
#the next line adds user to a group
net group %4 %1 /add /domain
#these commands create directories on the file server
#that will be used for home directories
md \\fileserver\users\%1
md \\fileserver\users\%1\exchange
wait 10
#this command creates a hidden share on the fileserver
rmtshare \\fileserver\%1$=e:\users\%1
#this command syncs the account databases so that future
#instructions will run regardless of where
#authentication happens
rcmd \\PDC net accounts /sync
wait 50
#the next two commands set the home directory
#and logon script parameters
net users %1 /HOMEDIR:\\fileserver\%1$ /DOMAIN
net users %1 /SCRIPTPATH:LOGIN.BAT /DOMAIN
#this last command sets the home directory
permissions cacls \\fileserver\users\%1 /G Administrator:F %1:F
cacls \\fileserver\users\%1 /G EVERYONE:R
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I then start with an excel spreadsheet of all the user names and make it so that the first column has 'newuser.cmd' in every row and make sure that the 'full name' entry is in quotes. I export the spreadsheet to CSV and delete all commas through 'find/replace'. Now I have a batch file that relies on the script detailed above to create as many accounts as I had listed in my Excel file with a mere mouseclick.
Some of the commands I use are from resource-kit utilities, so make sure that's handy.
ShackDaddy