Lingerie, Gloves and Clothing
(Most of these places carry a lot of plus size.)

Big Girls Lingerie
Dark Garden
Delicious Corsets (and that's the truth!)
Fetish Flair All kinds of fetish wear
Flirt Catalog
Gaspar Gloves
Gloves Online
Gothic Styles
Hips and Curves
Honour Plus Sized Latex
Leather Gloves on Line
Love Your Peaches Lingerie for those over size 14
Miss Martha's Corset Shop
Paul C's Leather
Pure Delish
Sonie's Creations
Spandex Wear I hate the kitty ears, but this may be what you are looking for.
Summit Fashions
Tough Gloves for tough men
Voluptugoth
Voluptuopus Vamps
XTC Leather Watch the quality, but some great looking things

One other thing--Patterns-- 

Simplicity # 8851 is great.

 On the cover is a French Maid, Little Red Riding Hood(with cape), a Pirate Lass, Nurse and a Saloon Girl. Well, and there is also a car hop but I don't know of anyone with that fetish :)

The pattern instructions call for these costumes to be made in cotton or normal synthetic cloth, but they would work just as well in PVC.  Instructions are so complete that you are told how to make (almost) everything except the shoes.  The pattern is based on three simple garments - a "peasant top" and a MINI skirt with a petticoat underlayer.

Best thing is that the sizes run from 6 to 20.  This pattern is still in stock.  I am not sure how much longer it will stay in stores since it is a costume pattern.

Crossdressing

All Heels For Men
Classic Curves
CrossDress
Crossdresser Closet
Crossdresser.Com
Cross Dress USA
The Fantasy Girl
Glamour Boutique
Janet's Closet
LD Fashions (great place for sissies)
Ruffles and Lace
Sinful Shoes
SuperSexy High Heels