When I started on computers in the 90's I initially depended on books in order to learn. Back then, the internet was not as developed as it today and eBooks were not really available. Even if they were it would have taken me hours to download one on a 28.8 modem.
Over the years I must have spent a ton of money on books. On average a computer related book is going to set you back at least $40. The problem with buying all these books is that the second you bring the book home the contents are already outdated. With the exception of a few topics like C++ and assembly which for some reason do not really change but still remain very important and relevant in the IT world. On my office bookshelf I have books on Java 1.1, Borland Delphi 4 and Oracle 8 just to name a few. At some point I stopped buying books from the bookstore because I realized that the "Dead Tree Format" was no longer working for me. With websites like Amazon, Safari Books Online and Scribd I can find almost everything I want without ever leaving my desk. Not to mention the eBooks are much easier to search.
The only thing that I do not like about eBooks is the fact that I usually have to read them while sitting at my desk. I always preferred reading on the couch with a cup of coffee or taking a book with me so I have something to do when I go to the mall with my wife. However, Amazon has answered this problem with the invention of the Kindle. Now you can read your EBooks anywhere.