Aside from having good listening skills, to be a good transcriptionist is to be efficient in your typing speed. There are a number of online typing tutorials and softwares to practice on. The very first software that I used was Mavis Beacon. It was so intimidating since a number of my batchmates in the MT Training were fast typists and I was definitely an average one. Some were slower than me, but the only thing I was eager and willing to do was PRACTICE.
Every morning, as I step inside the computer lab, I would start pressing the keyboard. At first, it really is very hard to memorize where to fix my fingers. Yeah, ASDF JKL; QWERTY UIOP....well, practice makes perfect they say and it is true. 
Here are some softwares you might be able to grab on to if you are serious in being a home transcriptionist. Time and speed is of the essence here and the more words per minute, the less time to accomplish, the more pay you get - but don't forget your quality.
Mavis Beacon Teaches Typing 18
Typing Instructor Platinum
Typing Instructor For Kids Platinum (Windows/Mac)
Typing Quick & Easy 17
TypeRightNow for Windows Includes Patented, Peek-Proof PC/Desktop* Keyboard Cover
Typing Instructor Platinum 21 [Download]
JUMP START TYPING
Typing Instructor Deluxe V17 [Download]
Typing Tutor for Dummies
Mavis Beacon Teaches Typing 15 [OLD VERSION]
