There are many books about diabetes.

Here are a couple of favourites;

Type 1 Diabetes in Children, Adolescents and Young Adults: How to Become an Expert on Your Own Diabetes by Ragnar Hanas

If you have diabetes or you are the parent of a child with diabetes, you have to be an expert on diabetes.  You have to live and breath the subject and continually improve your understanding of why blood-glucose levels go up and down - often seemingly for no apparent reason.

There is no such thing as perfection in understanding or controlling diabetes.   However, this book is  the best thing we have come across at explaining how to manage the condition.   It covers lots of technical detail but explains it in plain English.

Carbs & Cals: A Visual Guide to Carbohydrate & Calorie Counting for People with Diabetes

This book also comes as an App for iphone users.  Very practical.  Just look up the food and it shows you various sizes of slice or portion and tells you what the carb level is.

As for magazines, make sure you ask for 'Linkup' from diabetes UK.  This is a magazine aimed at parents of children with diabetes.