Oh y'all: it occurred to me to search Etsy for Dr. Horrible costumes (I found a few things that aren't costumes, too):

http://www.etsy.com/view_listing.php?listing_id=31369482
 available in adult sizes, too: http://www.etsy.com/view_listing.php?listing_id=33102548
http://www.etsy.com/view_listing.php?listing_id=32374396
http://www.etsy.com/view_listing.php?listing_id=32672029
http://www.etsy.com/view_listing.php?listing_id=32515325
http://www.etsy.com/view_listing.php?listing_id=30931064

and my very favorite:
http://www.etsy.com/view_listing.php?listing_id=30964273
(because racy sayings in cross-stitch rarely fail to amuse me)


And my Corpse Bride icon reminds me that there are lots of other costumes over there; that's because I have a secret yen to be a goth bride:
http://www.etsy.com/view_listing.php?listing_id=31443992
http://www.etsy.com/view_listing.php?listing_id=20364586

plus there's the punk-rock tutu ("As seen on Good Day Sacramento!!"):
http://www.etsy.com/view_listing.php?listing_id=33098807

and more normal stuff too:
http://www.etsy.com/view_listing.php?listing_id=33092495
http://www.etsy.com/view_listing.php?listing_id=33110142
http://www.etsy.com/view_listing.php?listing_id=32752821

(and I guess I should say while I'm on this Etsy tear that my store is live, too, although there's only one item there at the moment. I'd wait a few days if you want something other than pink glass.)