I learned the bulk of my Linux knowledge from this book back in 2000, when I found it in New Zealand - boot sale or some such - so great to see it available and so cheap @£5! Spent years trying to find it since, and now have it again.
If you want interactive learning from beginner to intermediate and just paste the commands in as you go, you can't beat Will Shott's pdf; TLCL-13.07.pdf
Highly recommended for an easy to read, but in depth view of the Unix/Linux OS, with a heavy leaning toward scripting. If you are into manipulating text at the most fundamental level, then this is the book for you.
A 1" thick text book paperback that will keep you busy for months...