Stumbled upon another Fiesta related blog, the Fiesta Online Costume Vault! I'm not sure how long this blog has been in existence, but from browsing it a bit, it's well put-together, clean, and informative. There are some great screenshots in there from both released and unreleased costumes... looks like someone's been messing with cash shop links! (I used to do the same thing! Just lazy to do so now.)
Anyway, if you're pixel-obsessed like I am, I suggest you stop by over there and have a look.