The Children's Orchard has to be one of my favorite children's resale shops. It's a nation wide chain and you can check here :http://www.childrensorchard.com/ to see if you have one in your neck of the woods.
Every so often Children's Orchard has one of my favorite sale, and from March 14-27 they are having this sale again. If you spend at least $25 dollars they will give you back half of your purchase price in the form of a gift card to use at a later date. So if you spend $30 dollars, you'll get a $15 dollar gift card.
I think this sale is awesome, because you can practically buy your child's entire seasons wardrobe for $25 bucks. I'll be making my list of what my kids need for the upcoming spring/summer season, and hitting this store this weekend. Can't wait!