gimpjedi
If you want to concentrate on Gundam Kits than I recommend Hobby japan and their publications relating to building Gundam Kits. Yep, they are in japanese but are easy enough to follow without being able to read/understand japanese.
Most of the other things you are interested in can be easily found by doing a search here on the forums or on google.
There is way too much material out there that we could recommend you as you are asking nearly for the full knowledge base about building models from the basics to the advanced techniques.
Work slowly, try a few new things on each model in a few years you will have mastered a lot and be able to build way better models than you can do now.
Getting good at modeling is maybe 5% reading about techniques the rest is trial and error and pracice, practice, practice and than some more practice.
HTH.