@SuperTwit
If you'd care for some free advice, I'd suggest you actually start with C, if you want to do a bit of Amiga development. The reason for this is that the NDK examples focus on C.
Once you are familiar with the basics of opening screens, handling input etc, you can then start looking at doing the same sort of stuff in assembly language. Even then, I'd say for non time-critical stuff, it isn't really worth it.
In the end, I favour writing in high level languages and only reimplementing those things in assembler which are either impossible (or impractical) to do in C, or where I feel that the compiler hasn't done a decent job optimising some critical piece of code. Integrating C and assembler is pretty straightforward, you just have to know what calling convention C is using, or failing that, write your own register-specific argument list when defining a C callable assembler routine.
Writing entire applications from the ground up in assembler is comparatively time consuming and can be very frustrating. Although, I have to admit, when you get an executable down to a few hundred bytes, there is an undeniable feeling of satisfaction
