User profiles:Domain vs. local

When originaly setup several of my users
only had local machine logins. Now they
have been added to the domain and
using their domain logins have access to
the resources on the domain. How can I
allow them to continue to use the
necessary resources of the domain and
access the programs installed from their
local logins, along with the accumulated
email stored in their Outlook profile .pst
files and associated with that local login.
And hopefully do it in as few steps as
possible. These are Dell laptops, running
Windows 2000.