Welcome to the Rogue world!
I recently set up a server where you can play Rogue online via ssh, and watch other people play. It's at
rlgallery.org. There are several players who are rather good, so there are definitely people with an interest in it.
Rogue 3.6 is indeed the oldest version that can be downloaded and played. The Rogue 1.0's on Dungeondweller are later ports to other platforms; the version numbers started over.
For tips/hints/etc., you should start by reading the "Vade-Mecum" on rogue.rogueforge.net. For an overview of the genre, read through the
@play column on GameSetWatch.
Have fun with roguelike history!