PUMA offers its PUMA Women's Soleil V2 Sneakers in four colors (Peacoat/PUMA Silver pictured) for $31 with free shipping. (6pm charges the same in Black/Dark Shadow.) That's the lowest total price we could find by $7. They're available in sizes 5.5 to 11, although not in all size/color combinations.
Various eBay sellers take up to 90% off a selection of athletic gear and shoes, with prices starting from $2. (The sale banner says up to 50% off, but we found higher discounts within.) Plus, many items bag free shipping. Some best bets: