Create new polling hosts and modify the tree using scripts?

[sparkyflashpants]

I have about 500 polling hosts I want to create. I don't want to add each one of them by hand. I've created templates for everything, so all I need to do is create a new polling host with the IP address I specify and have it use the default templates. Is there a way I can create new polling hosts using a script? I guess I could modify the MySQL database directly using a script, but I'd be worried about breaking the database...

Also, I want to dynamically change which graphs appear in the tree. What I want to do is have an "Active" section of the tree that just contains the graphs of hosts that have seen activity in the past few hours. I have a script that calculates which hosts are "active" hosts and I want that script to update the tree to show only the graphs of those hosts. Should I just edit the SQL database directly? Or is there a php script or something I can run to clear out all graphs under the "Active" section and then insert all the active hosts?

Thanks!

RedHat 9
Cacti 0.8.2a
rrdtool 1.0.45