These links have been very useful to me as I've begun to explore more of a vintage look for myself. Expect this list to grow in the coming months.
All-Purpose Vintage
Fashion Flu.com: Fashion Flu isn't specifically vintage, but they do vintage articles and features from time to time. Fashion echoes from vintage styles can also be advantageous to the vintage afficiando. Fashion Flu also features a lot of good hair and make up tips for a variety of styles.
Glamour Daze: This well-designed blog is totally devoted to vintage fashion and make-up. It looks to be an invaluable resource.
The Lisa Freemont Pages: This blog has EVERYTHING. Youtube how tos, product reviews, fashion, hair, and make up, and an amazing collection of links to other places that help you live the vintage lifestyle.
Quaintrelle Life: Beautiful pictures of vintage fashion as worn by the blog's author; a shop which sells vintage clothing. Of special note are the hats, faux furs, and evening gowns.
Vintage Life Magazine: One of the many things the Brits do better than us. You can get a web copy if you're out of country. I'll be doing that in the next couple of weeks. See what the fuss is all about with a free preview of the February issue.
Clothes
Bettie Page: I bought a Bettie from Mod Cloth, and I love it. Bettie is kind to us large women. Her sizes go up to 4X, which is about the vintage equivalent of a 22.
Blue Velvet Vintage: In addition to selling Bettie Page and Trashy Diva, BVV has its own line, and specializes in the 1920s as well.
Cats Like Us: Some kitsch, some clothing, but is a good clearing house for learning about vintage and retro designers.
eShakti: This website has clothes that are inspired by vintage. The dresses are superlative. Clothes can be customized to your measurements, as well as purchased in standard sizes. The site specializes in providing clothing of all sizes from 0-26W.
GetGoRetro: All about the 50s. You rock-a-billy people pay attention.
Heyday: While the dresses aren't all that, the pants look pretty impressive.
Le Bomb Shop: Ebay Shop with Retro Clothing. Some items are a little meh, but there are some good 50s and 60s style sundresses.
ModCloth: My friend Julie turned me on to their long dresses section, which is where you will find most of the vintage looks. Sizes go from small to 4X. These are some beautiful dresses, and cover the style of a lot of eras.
Mode Merr: Beautiful clothes overall, but an especially wonderful collection of shirts and skirts.
Pin-Up Girl: Focuses on that 40s pin-up look, with a variety of brands at its disposal.
reVamp Vintage: Recreates looks from the 1910s until the 1950s in limited designer runs. If you want something unique, and you're willing to shell out for it, this is the place to go.
Stop Staring!: A versatile vintage reproduction shop with a wide range of styles and sizes. The site is even classified by category so you can go in looking for 40s, 50s, or Rockabilly clothing.
Trashy Diva: New Orleans based vintage fashion company, with an emphasis on wearability as well as design.
Hair
Stage and Screen Hairstyles: Introductory stage hair styling book with some vintage options.
Vintage Hairstyling by Lauren Runnells: How to do hair from the 30s, 40s, 50s, and 60s.
Make-Up
Stage and Screen Make Up: Introductory stage make-up book with some focus on vintage.
The 20-40 Style Makeup Guide: A website guide showing styles and color palettes of the 20s, 30s, and 40s.
Besame Cosmetics: Cosmetics for the vintage look. I'll be buying some of these and reviewing as soon as I can.
Blush Vintage Make-Up Tutorial Disc: Looks like this disc rocks. It'll take you from the 20s to the 80s.
Dita Von Teese 40's Style: Dita rocks a New Year's look, and gives you a solid how-to.
Retro Make-Up by Lauren Runnells: How to do make-up from the 30s, 40s, 50s, 60s, and 70s.