The Frankfort Arsenal tumbler is probably the best buy on the market - especially when you can pick it up on sale at MidwayUSA like I did.
For media, I like to use walnut on the fresh-fired cases for a couple hours before doing anything else. Then, with pistol cases, I resize/decap them, expand the mouths, and then toss them into corncob media until they are nice & shiney. Now they're ready to load after making sure there is no media stuck in the primer flash holes.
For cheaper media, you CAN use the pet sotre stuff. I picked up a bag of Lizard Litter, which was the perfect size walnut. The corncob you get there usually is too big (or at least bigger than gun specific media) - BUT you can pick up a cheap coffee grinder at Wally World and grind it down smaller if the larger size isn't getting the job done to your satisfaction.