In an ASP page to get the currentusers team or the selected users team you can access this with the normal GetContextInfo method.

var intTeam = eWare.GetContextInfo("user", "user_primarychannelid");

var intSelectedTeam = eWare.GetContextInfo("selecteduser", "user_primarychannelid");

But to get the team selected directly then you will need to access the keys in the QueryString. The Team is held in key5, so you would access this with

var intTeamId = Request.QueryString("key5");