Orchids for Dummies is a great resource and gives a basic overview. It was my first book and I still refer to it.
Miracle Grow Complete Guide to Orchids is also very good and a step above the Dummie book imo. I like this book probably the best for a general, fairly comprehensive overview on orchids.
Both of those books are easy to find, priced reasonably, and give you good direction regarding cultivation, repotting, and pests.
Once you get further into orchids (notice I did not say "if"
) you can look at some more expensive, detailed items for your library