Just finished reading Depth Sounder Secrets - Rick Huckstepp, and i must say it is an absolutely awesome read.
For the novice the book is filled with a lot of colour illistrations and very basic terminology that everyone can read and understand with out saying "what".
It answers all your basic questions about your sounder from how to set it up with your sounders options and then how to interpret what you see on the screen.
Go out and buy this book now if you want to learn to catch fish