mainly exploring is how to discover these things
visit a colonist scrap yard and talk to the vendors. they buy a variety of different craftable items.
brotherhood of farr bazaar POIs on desert planets in their territory. u can make a decent profit selling HV tool turrets.
gas refineries will buy advanced generators for very lucrative profit
u can also stuff just about everything in the F2 Factory and crap out anything. go into creative mode and make a starter block with a few devices u want to sell or even store in the OCD.
here is a guide on filling the OCD with extra stuffs that can be deconstructed and recrafted into just about everything