No where. You either need to find a commercial pattern and alter it, or learn how to draft/drape your own pattern.
Look at the forums at cosplay.com (or another website like that), and you should be able to find plenty of tips from other cosplayers.
Ebay
This is all I can find: http://www.cosplaymagic.com/nashabcowig.html
Your local michaels or Joannes are good bets.
Try cosplaymagic.com ~ see the related link below .
Sence its anime its not costumes its cosplay and ebay has good cosplay on it just look there then try looking on google for other websites if ebay has nothing good
hobbylobby.
I don't believe that there are much stores that sell Final Fantasy 10 cosplay costumes, so your best bet would to be checking online. Online stores have great selections of Final Fantasy cosplay costumes.
if you like superheros you could do Batman, Nightwing, Robin, and Batgirl.
Ohlees cosplay mascot is a professional production company, their product quality is very good!
its just like how a lot of people are wearing skinny jeans right now, they themselves love the way they look and are therefore popular among fashionwear; bleach is the same. People like the plot of bleach, therefore they watch it and enjoy it, and cosplay the characters. Maybe you should try watching it too, its a good show.
This is what I found, you can have a try on cosplayshow.com a good website for cosplay costumes
Yeah, her shoes are unique. I searched her cosplay costume on QQCosplay, check it out: http://www.qqcosplay.com/NSN/nsnkonblk.html Hope that helps. ^^ Good luck with your cosplay.