The definitive OpenVMS security manual is called the OpenVMS Guide to System Security.
The OpenVMS System Manager's Manual, Chapter 7, discusses aser accounts.
The various system management utilities referenced in this chapter (i.e., ACCOUNTING, AUTHORIZE, SET, SHOW, and SYSMAN) are described completely in the OpenVMS System Management Utilities Reference Manual.
OpenVMS Management Station Overview and Release Notes includes disk and printer management functions besides account management.
The Website www.multimania.com/pmoreau/decw/decw.html is the source of many freeware Motif packages that may interest the system manager.