I recommend the Bennett St School hands-down, and another good choice is to join the PTG, from whom you can obtain excellent materials and develop helpful contacts. I started with the Randy Potter school, but had the advantage of old friends who were in active in the Guild and helped us by letting us apprentice, and we joined the Piano Technicians Guild as Associate Members. Today's materials from the Piano Technicians Guild are, in my opinion, outstanding. If you will associate yourself with a PTG chapter, you can purchase these materials *and* find folks who may help you. You can find a local chapter by contacting the home office at 816-753-7747 or email to 75032.3711@compuserve.com. Direct your inquiry to Sandy. The cost has been most reasonable, and you get to meet a wonderful bunch of people.
This PTG archive page provided courtesy of Moy Piano Service, LLC