Making herbal tea blends can be a healthy and delicious passtime! The first thing you need is a good reference guide on the health benefits of herbs and the taste of each herb. That way you can know which herbs combine best! I have several books on herbal teas but my absolute favorite is the one below:
Healing Herbal Teas: A Complete Guide to Making Delicious, Healthful Beverages by Brigitte Mars.
This book contains 40 herbs and their medicinal and magickal effects – including categories for taste, acidity, etc. Its a great book if you like to blend your own teas – just pick and choose the herbs you want and start experimenting! The best part is – all of the herbs in this book are safe!