I always had problems with "Dummies" books because they all seemed to give you enough information to get you into trouble, but not enough to get you out. There are various FAQ's web sites that have good information well organized and understandable i.e. http://www.solar-electric.com/deep-cycle-battery-faq.html which you will find if you do a search on "battery faq" and you will also find http://www.batteryfaq.org which will tell you who makes which battery which is also useful.
A great deal depends on how handy you are, do you know how to use a VOM/multimeter to diagnose electrical problems, are you comfortable doing electrical work? Long story but I had to complete the electrical and plumbing in our trailer so I am intimately familiar with both system.