Amazon.com: Do-It-Yourself Trombone: The Best Step-by-Step Guide to Start Playing by Matthew Shephard with online audio and video demos: 9781705102664: Shephard, Matthew: Books
14 Websites To Learn Trombone Lessons Online (Free And Paid) - CMUSE
Online Trombone Lessons - Meet your teacher on Skype or Zoom | Your Space Music Lessons