Link Dump:

Paizo forum threads where fashion is discussed:

• Requests for a book about the regional fashions (plus architecture and other cultural artifacts) of Golarion: http://paizo.com/threads/rzs2mvdz&page=2?Fashion-in-Golarion
• Fashion in Varisia. (Jacobs weighs in)  http://paizo.com/threads/rzs2hug9?The-Fashions-of-Varisia
• Azlanti fashion (Hodge weighs in)  http://paizo.com/threads/rzs2pr9w?Concerning-Azlanti-fashion
• Golorain fashion (Mona weighs in) http://paizo.com/threads/rzs2ik0g?Request-For-Information-Golarion-Fashion
• My insane, fashion-based Conspiracy Theory gets shot down by Jacobs:  http://paizo.com/threads/rzs2qy8b?Thassilon-and-Shory. On the other hand, James Jacobs shot down my insane fashion-based conspiracy theory.

Pinterest:

• Schneider’s awesome Pinterest page of the fashions of Ustalav:  http://www.pinterest.com/wesschneider/ustalavic-fashion/ This page “won the internet” for me the day I found it. It’s a great mix of DeviantArt drawings, steampunk clothes, movie costumes, and Runway fashion.
• Some goblin has a way better job than I do:  http://www.pinterest.com/pathfinderrpg/
• My Golarion Fashion Pinterest page.  Because of course I have one.  Where I store the fashion that I may eventually get around to writing about.  It’s divided by region, with a special board for the Evil Queens and Empyreal Lords and for the Iconics.

Other sites and blogs:

• Fashion inspired by TTRPG monsters:  http://dungeonsandfashion.tumblr.com/