Check out The Whole Beast by Fergus Henderson not only will this book show you how to prepare various types of liver, it will show you how to use other parts of the animal you wouldn’t normally see/use.
I find this a pretty good resource for tough-to-use cuts... I've cooked a lot from it, and always found it good for instructions on how to make the most of the animal....
http://www.amazon.com/Whole-Beast-Nose-Tail-Eating/dp/0060585366
Hope you got the marrow bones, they are phenomenal with toast.
My wife got me this book for my birthday last year. This year she's getting me this
Define "disgusting". I cooked some lamb's nuts earlier today that my wife won't touch but my 13-month-old daughter loves. I cook offal all the time and though my wife both likes haggis and bought me Henderson's Nose to Tail Eating, she won't even eat simple red-cooked heart.
So what's disgusting? Marinated brains? Testicles? Kidney stew? Lutefisk? Sheep-shit-smoked herring (Taðreyktsild)? Dog? Mealworms? Monkey brains? Which? And more importantly, WHY is it disgusting to you?