Second Edition is online and follows Racket's versioning:

http://www.ccs.neu.edu/home/matthias/HtDP2e/

I have a hard copy of the first edition. The square format single column layout reduces readability. But the methodology seems to be based on sound engineering principals.

I'd probably recommend Kiczales's Systematic Program Design MOOC as a good extension of the HtDP program methodology. https://www.edx.org/course/how-code-systematic-program-desig...

How does it compare to SICP? It's hard not to see the similarities : an introductory MIT book about programming written in Lisp.

> How does it compare to SICP?

Both are intended for beginners, but HTDP probably a bit easier as compared to SICP.