How to find books useful for costuming
There are three main places that you can find books useful for costuming:
GT's (GT495 - GT2370) - second floor: These are the social/anthropological history of dress items. Here you will find books on say, the veil in 21st century France, the history of the corset, and illustrations of working clothing in England from 1400-1600.
PN's (PN2000 - PN3307) - third floor: These are techical theatre books. Good for stage makeup, but surprising low on costuming.
TT's (TT490 - TT999) - third floor: These are the books on fashion, designers, the apparel industry, and the technical skills/processes involved in clothes making (i.e. pattern books, tailoring, hatmaking, knitting patterns).