Here are some of the websites I frequent... and by frequent I mean check daily.

Slick Deals tells you where the best sales are online as well as coupons

Woot offers one item per day at an extremely low price

Money Saving Mom tells you where to use your coupons and where to get freebies

Deal Seeking Mom also offers coupons and freebies

Groupon offers one great coupon for your area per day