In the last 5 months I've gotten:
Eat, Drink & Be Vegan: Great Vegan Food for Special and Everyday Celebrations
Vegan Planet: 400 Irresistible Recipes with Fantastic Flavors from Home and Around the World
Vegan Soul Kitchen: Fresh, Healthy, and Creative African-American Cuisine
Vegan Vittles: Down-Home Cooking for Everyone
Vive le Vegan!: Simple, Delectable Recipes for the Everyday Vegan Family
You Won't Believe It's Vegan!: 200 Recipes for Simple and Delicious Animal-Free
Prior to that, I added about 5 or 6 new books. Since I only used 3 cookbooks the first 2 years of being vegan, and now I have about 20, it's been an adventure having so much variety. (I've been vegan for 3 years this May).
The advantage to having so few cookbooks in the beginning was 1) I really got to know the recipes and books inside and out and 2) I was lucky enough to have picked excellent books so I was spoiled. The recipes were delicious, varied, and easy to follow.
I never really cooked before going vegan so I am especially grateful to my early books for helping me to build my confidence.
In case you're wondering, these were the books I loved so much:
The Mediterranean Vegan Kitchen
Vegan with a Vengeance : Over 150 Delicious, Cheap, Animal-Free Recipes That Rock
Later, I added Veganomicon: The Ultimate Vegan Cookbook by Moskowitz & Romero.
So far I've loved the books by Dreena Burton (particularly Eat, Drink & Be Vegan) and, surprisingly, Great Chefs Cook Vegan. The recipes have been easy to follow (even though they can be really involved) and the outcome excellent. Vegan Planet has also been consistently great.
The others I'm still getting to know and haven't been a grand slam every time. They've involved adding more spices or me wishing I hadn't done a step.
I usually cook 2-5 new recipes a week so I'll use this blog to document the results.
Happy cooking!