It's definitely a good idea to find out as much as you can before you bring piggies into your family!
I'm not familiar with that particular book. It's been awhile since I've bought actual books on guinea pigs as there is so much up to date information online (with links to these elsewhere on this forum.)
When I was fairly new to guinea pigs, I found this one to be good:
[ame="http://www.amazon.co.uk/Really-Useful-Guinea-Pig-Guide/dp/1852791276/ref=sr_1_1?ie=UTF8&qid=1302728700&sr=1-1"]http://www.amazon.co.uk/Really-Useful-Guinea-Pig-Guide/dp/1852791276/ref=sr_1_1?ie=UTF8&qid=1302728700&sr=1-1[/ame] "The Really Useful Guinea Pig Guide" by Myra Mahoney.
It has some very cute cartoons in it as well. However, some of the info might be out of date. I see that she's done a new one as well, which is here:
[ame]http://www.amazon.co.uk/Mini-Encyclopedia-Guinea-Pigs-Mahoney/dp/184286226X/ref=sr_1_2?ie=UTF8&qid=1302728700&sr=1-2[/ame] "Mini Encyclopedia of Guinea Pigs" but I haven't read that one either.
Peter Gurney's books have always been excellent and my second pig, Warren, came from Peter. However, it may be that some of the advice in these is also a bit out of date.
I remember he was quite critical of a number of piggie books on the market where the advice wasn't exactly sound - for example suggesting it was okay to house rabbits and guineas together or bad advice on feeding. Whatever book you find, if there's anything that you feel a bit unsure about, it's worth asking here just to be on the safe side.
Good luck!
lots of nice pictures too which helps! I've read all the books at work x