I used to do just pliers and boxcutters, but I treated myself to a jin tool this winter and I'm happy I did! Dang, that thing shaves as easy as a razor. Makes removing old and dried up bark a lot easier.
The Rudyban carving tool is made by no other than Rudy, from Italy. Rudy is a student of Professional Bonsai Master Mauro Stemberger. Mauro made this tool super popular by using it on a regular basis. This tool has quickly become one of the most important tools in many bonsai practitioners...
www.superflybonsai.com
If you are getting into larger carving a Beavercraft chisel set or similar is a great start.