I reviewed another of Jaffrey's books here, and mentioned a book on Indian spices was needed. I thought I had every one of her books, but this little one had escaped me. This book is great. It allows you to research the spices needed for cooking so you can make a list to shop on [...] or other site to get exotic spices at decent prices. Still, the book doesn't really talk about how, say, curry recipes are personal. Evidently, people mix their own for family preferences, various meats or vegetables. I guess you just need to get familiar enough to experiment, and I'm a long way from that place.
This is what I would call a handbook (although it has many good recipes) that should take a spot right next to all your Indian cookbooks. Get this and keep it handy.