We'd been talking for awhile about spending a month or so trying out a new cuisine. We'd finally settled on Indian (in general, not focusing on any of the regions in particular). The first cookbook we picked up (at Powell's, on a trip to Portland to see Ben's art show) was The Art of Indian Vegetarian Cooking, by Yamuna Devi.
It's based on Vaishnava cooking traditions, according to the introduction. It's quite an interesting cookbook, in addition to being vegetarian there also doesn't appear to be any onion or garlic.
As part of the reason for diving headfirst into a new cuisine was to learn new techniques, ingredients, and tastes, this book seems to fit the bill admirably.
It's also quite enjoyable reading, the recipes are proceeded by text that sometimes tells a short story, and other times gives advice on presentation or accompaniments.