As a costume designer I find a lot of items on ebay to use in shows.  Mostly from the vintage areas but still a lot of items that are contemporary will work really well too.  When you are looking for something in particular you can use a variety of key words in your searches.  For example, if you are looking for victorian goods you can use terms like Victorian/Historical/Edwardian/Vintage/Dresses/Shoes/hats.  This will pull up a variety of items that will most certainly work for you.  The possibilities are endless. I have costumed 2 shows in 2006 so far, just from ebay purchases. The Vintage sellers on ebay are knowledgeable and helpful. If you are wanting a certain look, you can almost always find something on ebay that will work on it's own or with a little creativity on your part.  From hats, to purses, to full outfits including shoes, there will always be something that works for whatever show you are planning, whether its is theatre or nightclub shows.