Here is Target's Recently Up-dated Coupon Policy:

The best way I've found at target to save is coupon stacking. Even better if the item you are stacking coupons for is also on sale!

Here is a link for Target's STORE coupons that you should be able to stack a manufacturer coupon with.

Finally, here is a link to their weekly ad, it usually up-dates a little after midnight Sat./Sunday