If you've decided that Linux is where it's at and would like to become more well versed, you might be asking yourself which books are worth the cost. Over the years, I've amassed quite a library of technology-related books. In this post, I'll briefly review what the book covers along with my opinion of its usefulness. I'm going to break the books down according to Beginner, Intermediate and Advanced users.
I would classify Beginner as that individual who has little to no exposure with Linux and who might need a bit of hand-holding until they become more acclimated.
The Intermediate user would be someone who has the basics down fairly well, can maneuver the command line, understands the filesystem tree and can at least know where to go to find the solution to their issue.
The advanced user can be classified as someone who's been there, done that. He/she has seen their fair share of obstacles and uses books more as a reference. He/she needs little to no help in getting their issues resolved.
It's worth mentioning, before I delve into book titles, that the distribution of Linux you choose should coincide with the kinds of books you choose. For instance, you wouldn't necessarily get a lot out of a book for Fedora if Ubuntu was what you've decided to run. That's not to say that you wouldn't learn something, but it just wouldn't be catered to the way Ubuntu does things as opposed to Fedora's.
If you search, you'll find info that covers what Linux distributions first came about and how future distributions built off of those core few. An example of this would be that Ubuntu is based off of Debian which was one of the original Linux releases. Eventually, you'll probably want to learn all you can about each core distribution, but if you're just getting started, it can definitely be overwhelming how all distributions handle things like package management, package installation, location of common configuration files and their locations and so forth.
Books for the Beginner (Ubuntu):
Online - Ubuntu Pocket Guide and Reference click here to download for free
Online - Ubuntu 10.10 Essentials click here to view
Book - Beginning Ubuntu Linux by Keir Thomas
Books for the Beginner (Fedora):
Book - Fedora 7 Unleashed by Andrew Hudson and Paul Hudson
Book - Fedora 10 and Red Hat Enterprise Linux Bible by Christopher Negus
Online - Fedora Linux Essentials click here to view
Books for Intermediate Users:
Book - Optimizing Linux Performance by Philip G Ezolt
Book - Running Linux by Matthias Kalle Dalheimer and Matt Welsh
Book - Linux Cookbook by Carla Schroder
Book - Linux in a Nutshell by Ellen Siever, Stephen Figgins, Robert Love and Arnold Robbins
Book - Learning the bash Shell: Unix Shell Programming by Cameron Newham
Book - bash cookbook by Carl Abing
Book - Classic Shell Scripting by Arnold Robbins and Nelson H.F. Beebe
Books for Advanced Users:
Book - Unix Power Tools, Third Edition by Shelley Powers, Jerry Peek, Tim O'Reilly and Mike Loukides
Book - Essential System Administration: Tools and Techniques for Linux and Unix Administration, 3rd Edition by Æleen Frisch
Book - Expecting Expect A Tcl-based Toolkit for Automating Interactive Programs (Nutshell Handbooks) by Don Libes
I'll update this more as time permits, but this should help get you started. If you're a tablet/netbook user, it's worth mentioning that you can push pdf's onto it and read straight on the device. Lots of pdf's can be found for free online, but the Safari resource from oreilly publications is an excellent resource. You can subscribe and use it as a virtual library. You can also convert html/chm formatted content into PDF as well.