Try Google Search for "Midi Learn" which gives a variety of sites.

When I started learning about Midi, I purchased a couple of books which gave me a grasp of the subject but I only began to understand the use and inter-relationship of Continuous Controllers such as CC1 Modulation, CC11 Expression and Pitch Bends when I started beta testing for the Russian Company Ntonyx in 1998. They have two products which calculates and enters relevant Midi data to tracks according to the GM instrument being used.

The major product is their Ntonyx Style Enhancer which is also included in the Jasmine Music Program and the cut down version, which I use, the Ntonyx Stylizer. You can switch track data between RealBand and the Stylizer via the Clipboard and do complete Midi songs or one track at a time. It is simple to understand and use whereas the Style Enhancer has a very long learning curve.

Lyn