NetID, Undergraduate to Graduate Transition
If this is a recent transition and you know your password, you won't need to do anything.
I was an undergrad and now I'm going to grad school, what do I need to do?
Your NetID will be the same as it was in undergrad, and you don't need to claim it again.
If you are unsure of your password, it can be reset via normal means (self recovery, call or visit the Help Desk).
You should be able to go through http://partnercomputing.illinois.edu/ to setup your Exchange account, but you may need to call the Help Desk and they can create one for you.
Your Google Apps account will eventually be deprovisioned, but there is no time table on when that will happen. You will be contacted if that date is set.