Found in 2 comments on Hacker News
qhoxie · 2008-11-27 · Original thread
Why's (Poignant) Guide to Ruby:

This is good for your first steps. Then check out The Ruby Way to dig in deeper:

silencio · 2008-08-03 · Original thread
I'm quite fond of while there are some people who love the pickaxe book (first edition is free on others.

As for free guides, I love pointing people to

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