IMO, the most important thing you should want to get from reading is enough knowledge to be able to ask intelligent questions and understand the answers. And this is a great place to try them out!
The other great resource I forgot to mention is... Compass Marine How To Articles
An online DIY guide to do many tasks aboard - especially those electrical / electronic related.
RC has done a great job of sharing his knowledge w/ us boaters. He's a professional ABYC certified electrician and can supply many of the components - I've purchased some from him as a "thanks" for his unselfish contributions...I figure if there is a price difference it's a small reward for his very worthwhile efforts.