I think the basics of any DAW are pretty easy to learn, as long as you have some guidance in the form of a manual and/or tutorials. It's like learning any complicated system...if your initial goal is to learn the program in its entirety - how
everything works and relates to everything else - then you're going to get overwhelmed and bogged down very quickly. However like most complex systems it can be broken down into smaller parts which are easier to understand in themselves. I'm pretty sure there's a "Zen And The Art Of Motorcycle Maintenance" type point I'm trying to make here.
In terms of getting up and running, all you need to know is how to set up your audio device, how to set inputs and outputs, then the basics of audio recording/playback. Then I guess how to work with synths and basic piano roll editing, as well as how to insert and use plugs, and the basics of the mixing console. All of that stuff will come to you very quickly.
When I first learned Pro Tools I took in as much as I needed to know to get some audio and MIDI into the program, and how to edit/mix it. Then I put the book down and started making music. I did exactly the same thing with Sonar. I find it helps to learn the program in conjunction with the creation of a experimental song. Once you have enough of the basics down to make a tune, you'll start to make one. And as soon as the creative juices are flowing, you're going to be led naturally into the other features of the program and learn how to use those too. In any case, that's how I generally learn how to use a program. Learn just enough to start being creative, and the rest will come in time out of necessity.
But that's me. Other people might prefer to sit down and read the whole manual back to back before they even start a project. I however am of the opinion that our brains are wired to learn by the practical method I've described above.