I've made a few dump cakes before, though that was either camping and someone had a special birthday or back in college where you didn't have any equipment and didn't want to spend the $ to buy any or keep any of it afterwards. I've also made them during extended power outages (Irene & Sandy) to entertain some neighbourhood kids. You just need a disposable pan, a box of cake mix and whatever toppings/canned fruit you want then add a cup of your liquid of choice

If you're ok with the taste and texture of boxed cake mix, you'll be ok with a dump cake. It's more of a hassle-free, fun thing to do especially in a power outage. You don't do it for taste.

I'm both amused and a bit disturbed that 1) someone thought there needed to be a cookbook for this and 2) someone thinks they need to buy a cookbook for this.