I think is ok, if you already know how to program. The SICP book is not the easiest book ever, but is also not that complicate. SICP teach you many things, not only lisp. YOu can also follow the lectures in the MIT open course web[1].
If you dont feel comfortable with the SICP book (many people dont like it), you can start with How to Design Programs(HTDP)[2]. It teach scheme/racket, and is one of the better books to teach programming that I've seen, and the people in the mailing list and irc channel are very friendly.
The good thing is that both of them are free[3], so you can take a look and see if the fit your expectations.
[1] http://ocw.mit.edu/courses/electrical-engineering-and-comput...