The Amazing Slow Downer Great for playing along with records and transcribing. Alters speed, and or pitch. SIT Strings These guys gave me a little endorsement deal, I've used their strings on all my guitars for years. Liberty Guitars (Resonators) This guy makes a variety of resonators and dobros, very reasonable prices too. Love mine and use it all the time. Harmony and Theory A good book on theory and harmony that I recommend to my students. The link is to the book's page on Amazon.com. Under $15..good deal!