There are four resource buildings, one for each resource. You can gain additional resource buildings by upgrading your outpost.
Metal Foundry - Produces Metal
Metal foundry requires 283 oil and 425 energy to be built.
Wind Turbine - Produces Metal
Wind trubine requires 283 oil and 425 metal to be built.
Gem Refinary - Produces Zynthonite
Gem refinary requires 425 oil, 283 energy and 283 metal to be built.
Oil Rig - Produces Oil
Oil rig requires 425 metal and 283 energy to be built.
There are four ways to gain resources.
1) Banking resources from your resource buildings.
2) Battling other players.
3) Capturing resource deposits.
4) Battling dracnoians in salvages.
Resources can be stored in warehouses, although outposts also have a small storage capacity.