Depends what you mean by "gourmet". If you mean by top-tier chefs, then you probably won't find a lot. if Alain Passard were ever to compile his vegetable/vegetarian recipes in a cookbook, it would surely go on this list. If you google around, you can find a bunch of recipes from him online. Check out this list for a few ideas:
http://www.amazon.com/gp/bestsellers/books/4336/ref=pd_ts_b_nav

Ammini Ramachandran's Grains, Greens, and Grated Coconuts http://www.anothersubcontinent.com/arecipes.html

May be too late, but here's one more vote for Veg Cooking for Everyone, and I also have the Bold Veg Chef by Ken Charney, though I don't love it. One more possibility: Meat Lovers' Meatless Cookbook by Kim O'Donnel: http://www.amazon.com/Meat-Lovers-Meatless-Cookbook-Vegetarian/dp/0738214019 don't own it, but heard it's awesome.

I echo the kudos for the Vegetarian Epicure books and anything by Deborah Madison. Annie Sommerville continued Madison's Greens Restaurant books with Field of Greens and another one I can't think of right now that are equally wonderful. I have also been enjoying Patricia Wells' Vegetable Harvest.

When I was cooking vegetarian, I loved using The Vegetarian Epicure Vol. 1 and 2 by Anna Thomas. They are older books, but can be picked up on eBay as well as Amazon.

Here's another one: The Bold Vegetarian Chef by Ken Charney. Very creative recipes.

Thanks everyone. I'm looking forward to going to the bookstore tonight!

Oh one I should add that has been written about extensively on this website (in the Tournament of Cookbooks) is called Plenty by Yotam Ottolenghi. Plenty is a collection of vegetarian recipes from Ottolenghi's colum in the Guardian's weekend magazine. I have his first cookbook, its truly wonderful. Plenty is his second cookbook. I would suggest reading all the reviews on this website in the cookbook tournament. I have already placed my order for it, just waiting for delivery!

Let's not forget Julie Sahni's "Classic Indian Vegetarian and Grain Cooking." I own about a dozen vegetarian cookbooks and this one is and has always been my favorite. ;o)

The Indian Vegetarian is one of my favorites: http://www.amazon.com/Indian-Vegetarian-Neelam-Batra/dp/0028622855

I also love The Vegetarian Epicure, by Anna Thomas: http://www.amazon.com/Vegetarian-Epicure-Anna-Thomas/dp/0394717848

I agree that just about any one of Deborah Madison's cookbooks is a winner, and if you don't have any I'd start with Vegetarian Cooking for Everyone. I believe it has won numerous accolades, including a James Beard award and a Julia Child cookbook award.

In 1975, when I moved to a vegetarian way of eating, I was a Gourmet subscriber and my cookbooks ranged through the world's cuisines. In that period, The Moosewood Cookbook (Katzen) and The Vegetarian Epicure (Thomas) became very popular, selling in numbers that far exceeded the vegetarian population because they were mostly concerned about reaching levels of taste and preparation that would please anyone. Books by Madhur Jaffrey and others continued raising the bar. New books from Moosewood Restaurant, The New Vegetarian Epicure, and Passionate Vegetarian (Dragonwagon) continue bringing not only foods that raise standards for taste and presentation, but also meet our more credible standards for healthy eating.
And last word, these books aren't about cooking vegetables -- vegetarians eat for life.

My go-to vegetarian cookbook is Vegetarian Cooking for Everyone by Deborah Madison. I also have made many yummy dishes from Chez Panisse Vegetables by Alice Waters.

There is a really good predominantly vegetarian restaurant in Victoria, BC, Canada, where I now live, and they have published a cookbook featuring food that is served in the restaurant. Everyone I know who has this cookbook loves what they have cooked from it. Check out the link on Amazon for more info: http://www.amazon.com/Rebar-Audrey-Alsterburg-Wanda-Urbanowicz/dp/0968862306/ref=sr_1_1?s=books&ie=UTF8&qid=1291237628&sr=1-1

Deborah Madison, Vegetarian Cooking for Everyone. Same author as the first Greens cookbook (which is indeed excellent) and many other books on creative vegetable cookery.

I have Mark Bittman's "How to Cook Everything Vegetarian," which I like a lot. And there's another one that i bought when I was seriously pursuing being a vegetarian that I thought was really creative, but can't remember the name right now. i'll look for it when i get home and add to the post.

Vegan isn't a concern. Thanks hardlikearmour! It looks perfect.

Pierino- I agree, I'm basically looking for something a little more than rice and lentils in various forms.

Personally, I don't think such a thing exists. However, you might want to look into EDIBLE: A CELEBRATION OF LOCAL FOODS by Ryder and Topalian (Wiley). It's not strictly vegetartian but has enough good dishes to qualify for those purposes.

The Greens Restaurant cookbooks. I have Fields of Greens. It has some delicious gourmet recipes, though not many are vegan if that is a concern.