You can get the membername by using the next statement:
strMemberName = Request.Cookies("Snitz00User")("Name")
And with the next SQL-statement you can get their 'real' name:
strSQL = "SELECT M_Firstname, M_Lastname FROM FORUM_MEMBERS WHERE M_NAME = '" & strMemberName & "'"
(Depending on some settings in the forum, this is the default I believe)
A user is logged in when the string strMemberName is not empty.