Multiple status maps?
Install nagiosmap on your central nagios server, and make the status map look any way you wish it to look.
But you will then have one status map only. Not multiple ones.
But simply create a user that is a contact for the "net1" and user2 is a contact for "net2" and so on. Now, login to the nagios website as user2 and he/she sees ONLY what you want them to see, even on the status map.
Remember, one status map shows everything, but 2 contacts can have 2 different looks or views of the network. That is exactly how I have it. I don't want some people to see EVERYTHING, so they are only a contact for SOME hosts/services.