Network mapping tool?

I'm looking for a network mapping tool. I found NMap on version
tracker, it sounds pretty good, but I'm wondering if there is atool like
this that has a GUI insteda of command line.

What I would like to see is the devices connected to my network, and
some info about what they are, ie. Airport card, bridge, whatever.

I remember seeing some program that would show the network address, and
what it was, but I can't remember the name, and I can't find it on
VersionTracker. I really don't need something like LANSurveyor, or
InterMapper, these programs do much, much more than I need, and cost
way, way more than I can afford for mostly idle curiosity about my
network.

Thanks

AndyD