Starting Forth by Leo Brodie is a classic book. Forth is a very elegant language. I came across a javascript implementation of it recently, which you can look up yourself :)
Currently my preferred language is Racket because it is so fun and practical, reminds me of the earlier days of Python but much more thought out. You write you code (which is fun) and you have an executable all within one setting.
I think the magic bit with Forth is that it's easy to see how to write one by the time you've finished Starting Forth.
I wish there was an easy checklist: Create stack data structure, create return stack, create primitives ...etc.