If you were raised in the "book" generation as Byron and I were, its disappointing the quality of books out there for the tropical fish hobbyist. Then add to this scenario (reduced quality books) stores that don't want to carry books, like Aquarium West - a local retailer in Vancouver - and the situation is down right depressing.
My philosophy on book purchases is this - reference books only; for the rest I leave to the internet and the library. Our local library has some decent introductory books on setting up tanks, a good fish intro, and a few books on the planted tank. So the obvious is to hit up your library first and read what they have a couple of times, use the fish books to dream... etc.
I have bought only one book, its another version of what Byron has recommended but is the grand daddy of them all; its "Dr. Axelrod's Mini-Atlas of Freshwater Aquarium Fishes (Revised Third Edition)." This book is authored by Glen Axelrod (son of Herbert Axelrod), Warren Burgess, Brian Scott, Cliff Emmens, Neal Pronek and Herbert Axelrod. This was "the" reference book for many decades in the hobby. On a humourous note, this is the fourth time I have purchased the same book (under different revisions however). I'm into my fourth time back into the hobby and each time I bought this book, giving it away when I left the hobby.
An interesting note on Herbert Axelrod, he was the "Man" who really got the ball rolling in North America concerning our hobby. He developed and grew the magazine "Tropical Fish Hobbyist" (TFH) and started the THF publishing empire; he was the "Tiger Williams" of the North American tropical fish scene. And just like "Tiger" he got into trouble, his was legal, I provide a Wiki link for you, it's interesting reading.
http://en.wikipedia.org/wiki/Herbert_R._Axelrod
Now would I buy this book again, knowing what I know now - the ecology of information in an electronic age. The answer is "no." I do use it a fair bit as folks like Byron like to use the scientific names of fish and I have to grab the book to see what Byron is talking about... lol... and in scenarios like this it is helpful. What I did instead was this: I like to read from pages, not the computer screen when I settle down to a "long read." And I examined my book budget, which is always generous, so I decided on a different course of action. I had a very good HP printer but the printer cartridges for it were to pricey, so I was like Scrooge printing items out. So I went out and bought a Kodak printer as the printer cartridges are almost free compared to other companies. Now I print out all kinds of goodies, and I organize these printouts into a binder - will be moving on to my second soon.
So for example, Byron has written - in the plant forum here- articles on the planted tank. I printed these out and have them at hand when I want them. I also usually re-read articles like his two or three times over a six month period.
Here is a link that will keep you busy and wear out your printer cartridge, but I really do recommend you print out the articles and read them, not just read them from the net. You will need to re-read some of this author's material a number of times, trust me on this, as its a heavy dive into the aquarium world. Also, though the information is excellent in his articles, his writing style leaves something to be desired and he obviously doesn't really proof read his stuff so some sentences are plain gobly ****. I'll link you to one article, you can surf his site and print to your heart's content, you will have lots of reading to do. I found his material so challenging (some of it) I have started myself on a Chemistry course (Chemistry for Dummies series) that I do at home (more fun when it isn't a school requirement); note: the book is from the library.
http://www.americanaquariumproducts.com/Basic_Aquarium_Principles.html
Have fun, if your area is like ours here, the selection of books available to you will be pitifully thin, so print from the net and start your own binder.