I would recommend a book called the Glucose Revolution: Glycemic Index Solution for optimum health (ISBN-10: 0733615007) available on amazon for less than £10. Although it does not tell you how much insulin to take, it helps you figure out how many carbohydrates there are in many different food and it even has a chapter on diabetes.
The first thing you need to learn, if you have not already, is how to read food labels. You need to know how many carbohydrates are in each portion of food and how to figure it out from the information presented on the packets.
Secondly, you need to learn how many units of insulin your body needs for every gram of carbohydrate you put in. For example; at present, i am taking 2 units of humalog for every 10g of carbohydrate in my breakfast, 1.5unit of insulin for every 10g carbohydrate in my lunch and 1 unit of insulin for every 10g in my dinner, but only if I go to the gym.
Sound complicated? It's really not, and it is something that you adjust to! plus this changes from day to day depending on loads of different life style factors.
Can your diabetic nurse refer you to the dietician at the hospital? If not, you could ask her for some carbohydrate counting information?
If this all falls though I could send you the carbohydrate counting information from my clinic, for you to have a look at.
I have been diabetic for just over a year, I still have a lot to learn, it's really hard at the beginning to know what information you need and where to get it.
Hope that helps!