Test Data Manager

How can I setup a user group that can be allowed to add users and then add those users to existing user groups. I don't want them to admin abilities?

trayrobbins

The Security -> Users and Groups function will grant the ability to make changes to users/groups:

Security Functions - CA Test Data Manager - 4.5 - CA Technologies Documentation 

"Maintain Groups and the functions that the groups can access, and Users and the Groups they are in"

So  you could create a group that has this function defined to it and then those users will be able to add other users... However, this isn't limited to a single group - they would have permissions to modify any groups. This might be more permissions than you wanted to give.