Go books are good as a secondary source of learning. Playing is most important. I have a fair number of books about go. Most of them are much like chess books I used to buy, full of very densely packed information, and hard to read. Most of the Diagrams were smallish, and made me want to rub my eyes after I stared at them. One series of books however was clearly better. The series is written by Janice Kim, a 1 dan professional, following the teachings of Jeong Soo-hyun, a 9 dan professional.
This series is simply beautiful in it's clear, concise approach, with full page diagrams (I have entire Go books that are smaller than the diagrams!). The difference is like night and day. I skipped volume 1 because I had progressed past it when I discovered them, but I bought Volumes 2-4. When I buy one I can't help but read 90% of the book within 6 hours of buying it. They are THAT easy to read. I have chess books that I bought many years ago in high school (when I was a chess nerd) that I still haven't read more than 10 pages of.
If you can't get to The Games People Play, (in Cambridge, near Harvard Square), her books are available through Smarkand's Web Site.