EMail Adx
What you can do is retrieve the domain and login name currently associated with the desired machine, then (if you have rights) access the GAL to return the set of values (usually only one, but there could be more) associated with the domain/login pair. I do something similar to this, looping through ADSI for computers, returning loginname, IP adx, and MACID. This allows me to send tailored email to the end users, pointing them to a little web app where I collect non-discoverable network information.