do they come with a recipe book?
I bought mine second hand on here so I didn't get one, loads of free info and recipes on the web. Have a look at babelfish5 on youtube for some ideas, Andy Howells blog has some good info too.
For meals it's pretty straight forward, avoid dairy for a start, you can get away with a few days or longer if it's frozen, but as a rule any fat is hard to dehydrate as there's little water content, it also goes rancid very quickly. Pre-cook pasta and rice before dehydrating, it rehydrates much quicker than cooking from fresh. Keep you chunks small, especially meats, I find minced beef and lean lamb to work best, chicken is better if it's shredded slightly.
Rinse off fat by placing cooked meat in a collander and then pouring a kettle over it.
I've just cooked large batches of chilli, curry, stew, bulked them up with plenty of carbs and calories and then dehydrated for 24 hours or so. once dried I weight them out into roughly 450-600g portions depending on how active I'm likely to be.