Thanks to both of you.
The main reason why I asked this question is that my IT staff does not wish to share any LDAP server information with me and is reluctant to support my use of LDAP (I think they are afraid that I will find out some way to make changes when I only want to make queries and/or they concerned that I will consume network bandwidth and LDAP server resources). So I really don't know how to provide any information for my query other than the implicit ability to be on the domain (already logged in interactively) and know the username to query. So, I will look again at the LDAP example URL provided and hope that I can generate the query I need with the minimal information that I have.
Ken