Once upon a time I had a spreadsheet of weapons resources, but of course I don't any longer. Perhaps someone will post a link.
Generically, you can look at schematics and see what goes into the popular items (FWG5, DX2 for pistol, I dont know others...) and see not only what resource, but what stats make it good. Find, save and put up for sale.
Or, hook up with a guild and make money with your friends. Either way, have fun playing