Unless you're selling back-to-school goods, your online sales are probably down, says writer and business owner Beth Cox in "E-commerce and the Dog Days of Summer." With the timely arrival of tax rebates, many apparel sites and other school-related products are seeing a surge in sales.

But what do you do when your products don't "suit the season"? Cox thinks she'll send out 10%-off coupons to existing customers during next year's dog days or target some of her best previous customers with special sales prices the slump.

Do your online sales suffer from seasonal slumps? What do you do to survive your "dog days"?