A really cool place I found when I was attending a Adoption Coalition meeting, a huge 2-story brick building that used to be a factory. Lots of the vendors had 25 or even 50 % off of everything in their booths.
The Shrewsbury Flea Market: fill a box for $10. I dug through boxes of junk for 3 hours! Sadly the flea markets if you even call them that in New England suck compared to Florida.