Amazon offers the BlueMagic 900 Carpet Stain & Spot Lifter 22-oz. Can for $3.88. Add it to your cart via Subscribe & Save and it drops to $3.30. With free shipping, that's a buck under our mention from a month ago, about $1 less than you'd pay in local stores, and tied with the lowest price we've seen.
Be sure to cancel Subscribe & Save after your order ships or you'll be billed for subsequent shipments.