As a guy who has been training solo for most of his life, here's my take on training from books.
There isn't always an FMA school right around the corner. Really good FMA schools are few and far between. If you want to study the knife, and all you can afford is read books, then it's better than nothing. However, while you may learn about knife fighting from books, it does not mean you will be a trained knife fighter. If you can find an FMA school that teaches knife, by all means sign up and train. Nothing can replace learning from a qualified instructor. If there aren't any instructors around your area, then attend seminars whenever you can.
If you are totally stuck and cannot find an instructor, I personally feel that videos and DVDs speak more than books. You can see the technique in action, how it looks, and how it functions. Here are the best DVD's to learn knife fighting from, in my opinion:
1) Shivworks Reverse-Edge Methods Volumes 1 and 2: These DVDs truly demonstrate the proper use of Pikal (revere grip edge in) in real confrontations. It's simply, brutal, and downright effective. This is quite possibly the best video on the subject of close-quarters Pikal. Here's the link to the trailer:
http://shivworks.com/videos/remv2.wmv
2) Atienza Kali Blade Simulator Volume 1: Demonstrates the Atienza Kali Blade Simulator with bolo knives...also shows video of the effects of the blade on boar meat. Here's the link to the preview clip:
http://www.atienza-kali.com/video/akbladesimdvdtrailer.wmv
3) Sayoc Kali 3 of 9 Template DVD: Demonstrates the Sayoc Kali 3 of 9 Vital template...this is great for understanding the importance of the knowledge of human anatomy:
http://sayoc.com/vidclips/30f9trailer01.mov
4) Jim Wagner Knife Survival: This guy is a law enforcement officer who has had many experiences dealing with edged weapons.
http://www.jimwagnertraining.com/store/KNIFE_1.wmv
Hope you find them to your liking.