Harley makes some nice products. Scratch and swirl remover and Harley glaze do a great job on most superficial scratches. They also have a thing called soft cloths which are lint free polishing cloths and help you get a really nice finish. Certain kinds of cloths can actually cause scratches too but these softcloths won't as long as they're clean.
For more significant scatches that Micro Mesh is really cool stuff. I stripped a guitar down to bare wood, sprayed it with Reranch rattle cans, and brought the finish up to this gloss using only the Micro Mesh. Follow their directions, keep it clean, and rinse often