I have recently purchased AGK2 along with the book in this link:
Teach Yourself Game Programming for Android and Windows [AGK eBook release]
Although it was written for AGK1, it will soon be having a free update for AGK2 so won't cost you more if you purchase now. The examples are still relevant for AGK2 as it is anyway.
I think also that AGK2 is good to learn C++ also because you can create some code in AGK2 then cut and paste to C++ and convert each line to C++, this doesn't need a great deal of work to change the code and I found it pretty straight forward doing this way. This will be where to go once you have gained experience with the Basic version of AGK2 though.
The good thing about the above book though is that it is about games and therefore interesting as some books are too BASIC and boring if you know what I mean.
Attached is a doc file tutorial for explaining loops / while / for next etc.
These is very basic examples and were written for DarkBasicPro but they can be converted to AGK2 and are easy to understand. They will give you an idea but again the above book is good.
Also I find these forums and the people on here are very helpful if you get stuck and someone will always reply to a plea for help with code that doesn't work.
Programming - AMOS on the AMIGA! / DBPro / Python / A bit of C C++ / now also AGK2! - Graphics - Deluxe Paint on the Amiga / Paintshop Pro / Photoshop / Lightroom / Grafx2
Previously worked for Prisma Software producing childrens educational software on the Amiga - Titles - Pepe's Garden - Paint Pot / Kids Academy range - Paint Pot II / Shopping Basket / Which Where What? / Blobs / Alvin's Puzzles