Hi -
Here is an excerpt from the link I'm including that should get you started:
"SASU for Version Upgrades
For customers who do not have a valid SASU contract and who are purchasing the upgrade to Cisco Unity Version 4.0, SASU services must be quoted based upon the new Version 4.0 configuration. Example: A customer upgrades from Cisco Unity Version 3.1 Unified Messaging, 32 sessions, and 1000 users to Cisco Unity Version 4.0. SASU would be based upon the comparable new Cisco Unity Version 4.0 system.
1. The customer would purchase the Cisco Unity Version 4.0 upgrade: part number UNITY40-SL32-VERUP. (Note: SASU is not mapped to the version upgrade part numbers.)
2. Comparable Cisco Unity Version 4.0 configuration would consist of:
a. Part numbers are UNITY40-SVRLIC-32 and UNITY-UM-USR-E (Quantity = 1000).
b. Associated SASU part numbers are CON-SAU-U4-SVR32 and CON-SAU-UMUSR-E (Quantity = 1000).
c. If customer is using Real Speak TTS, the product part numbers are UNITY-RS-2ML, UNITY-RS-4ML, and UNITY RS-6ML.
d. Associated SASU part numbers for TTS are CON-SAU-RS-2ML, CON-SAU-RS-4ML, and CON-SAU-RS-6ML."
http://www.cisco.com/en/US/customer/products/sw/voicesw/ps2237/products_quick_reference_guide09186a008011c984.html
The UNITY-BUNDLE includes the software AND server, if you want that. We don't do it that way, we purchase the hardware separately from our own vendor contracts and purchase just the Unity software and UM licenses. The Unity CD/DVD will have the Exchange install on it as well. You can use the Dynamic Configuration Tool to prompt for all of the install options, depending on whether you are doing VMO or UM. And I would ask your Cisco account rep to assist :-)
Ginger