1. Very! Many of the teachers are active on the forum and there are individual forums where you can contact the teachers directly. On top of that, there is a community of guitar players and students like yourself that use this forum every day. You can also chat on here (ala FACEBOOK, AIM, etc.), and ask as many questions as you want. You are in great company I can assure you! :eek:
2. You will learn the basics, but when you say you know nothing about music, can you be more descriptive? Are you brand new to guitar or just the idea of reading music and theory? From what point are you starting? :confused:
3. There are some lessons on Flamenco style on the site and the site is always growing with new instructors and lessons all the time. Once your signed up, check out this lesson on Flamenco style strumming. :D
4. The best way to gage this is to assess how well you move from lesson to lesson. Almost all the lessons on Guitar Tricks are set up in a "start to finish" format that guides you step by step through the lessons. You don't just get one lesson on a subject, you get a whole tutorial that starts from point A and ends at point B. You can also submit videos of your playing on the forum (as many people do), as well as ask as many questions as you want to users and teachers. :p
Best of luck and hope to see you on the forum in the future.
Douglas Showalter