I get coupons every other month or so from Lowes, not Home Depot. $25 off $250+ and $10 off $50+ purchase. I have used those $25 ones several times (3 new toilets in the last year, we have been renovating the bathrooms).
I also like the Lowes credit card, I get %5 off all the time. (and it is just a Lowes card, not a Visa or MC, so I don't get in trouble with it!)
I don't think HD "does" coupons, a friend who worked there told me that, he also said that sometmes you can get them to knock some off if you have a lowes coupon, bt you have to go to CS, they won't do it at the regular register.