If only has a .obj, then that's something you'll have to import. .obj files, for Poser items, normally go in the geometry, but you'll have more than just the .obj (and the template as well). If it was a prop, you'd also have a .pp2 file to go with it. You can always import whatever that may be, and then save it in your library (just add it, click the "+" and it'll jump into your library) and you can use it later by just opening the library and adding it. Hope that explains some things.