ShopItToMe.com, which scours sales at more than 100 online retailers.
Dozens of sites like RetailMeNot and Bargainist collect promotional codes for discounts on Web purchases. To find them on your own, try Googling the name of the shopping site with the words “coupon code” or “promotion code.”
Many retailers offer free shipping promotions from time to time or have thresholds at which they’ll ship for free. But, some of my favorite online shops such as Endless, RevolveClothing, Shopbop, and Piperlime, always offer free shipping.
See more by Farnoosh Torabi at Moneywatch site