Why do I find this system so complicated?
No idea why you
find this system so complicated. Most people would rather not carry the book around.
All OSs have the same sort of documentation - the main difference is that the linux man pages are much more technical than the "help" menu hints of other systems. Still, systems like Ubuntu have a help-system of sorts.
Being a new user of Linux/Ubuntu, for me, requires a manual that can be carried around while in transit to or fro work and home. Is there a manual other than online in forums or the documentation pages that can be used for someone who has absolutely no clue of this system but would love to learn and utilize this system?
You want a text book to learn from or a reference?
There are indeed many.
You need to take care with them though, the rapid development time means that by the time a book makes it to print it is probably out of date. Still, they can be handy - many gurus here started out with the "for dummies" books
You have specified Mandriva in your first post and Ubuntu in your followup. Which is it?
You have a reply for Mandriva:
a whole range
... all of these are out of date - note that "Ubuntu Linux Essentials" on that page has an online edition
which is up to date.
- all the electronic copies can also be purchased as regular books...
The best approach to print books is to find a technical bookstore with a range - pick off the most recently published titles from the shelf and try reading them. Buy the one you can most easily understand. A really good test is to see if the book covers a problem you have already struggled with (and know the solution to).
However, most people who are already used to other computer systems just need a crash course - for familiarization. You probably just need to wrap your head around the way things are done. Here's one for Ubuntu [pdf 334kB].
The exercizes take 6-12hrs to complete.