[mehulved]

Well 'The Debian System' isn't exactly a book that you should start from. You should go for this book if you like Debian GNU/Linux. This book isn't just about the operating system, it's also about the history, philosophy and the people behind the debian project. So, it's something direct more towards a entusiast than a end user. It does have a lot on debian administration and such too.
So, if you really want to know about debian indepth then this book is a good place to start with.
And can't you get an external modem? That should help you get started with net in linux. Make sure it works well with linux distros.