I would also recommend Tabledit. It is an incredibly powerful tool that allows you to enter either tab or standard music notation, and it will fill in the other.
However, it is not very instinctive, and is therefore really frustrating when you first start using it. There is help available, and if anyone gets it, I recommend Stephen Seifert's extensive Tabledit Tutorial , which he offers free on his website. Secondly, the Arranging for Dulcimers group here is available when you have question (and you will have many!) about how to use the software. You'll notice that I've posted a few questions there myself.
There is a free version that you can use which has certain length limits, such as only songs of 16 measures or something like that. However, if only those who had success with that free version bought the software, no one would do it. As I said, it is not obvious how to make certain basic indications, such as triplets or slides or alternate endings. You will drive yourself crazy trying to figure that stuff out. However, the resources above and general Google searches will get you answers quickly. And the more you use it, the faster you get.
Using Tabledit has made me a better player by helping me connect what I play to standard music notation and basic music theory.
--
Dusty T., Northern California
Site Moderator
As a musician, you have to keep one foot back in the past and one foot forward into the future.
-- Dizzy Gillespie