Maps - Descent 3 Source Port Game Tracker

Where to get Descent 3 maps in the Piccu Engine era

My 40PPS DJ servers rotate maps found in this set: Mixed Bag
The largest repository of Descent 3 maps is Sectorgame.
The place to find NEW, RECENTLY PUBLISHED Descent 3 maps is Descent Mission Archive (DXMA)

That should cover 99% of the maps you'll encounter in multiplayer servers. Just in case, here are a couple more mission repositories: Pooterman D3 Fischlein