Pampers Softcare Baby Wipes 7 pack box (504 wipes) for $14.64. With 20% S&S discount it comes to $11.71. Clip the $0.50 coupon at the bottom of the page and get them for $11.21. This is the cheapest I have seen in a long time.
Also coupon.com has coupons for pampers wipes and diapers. Print them and use them on in store sales.