I have no tips, but my oldest daughter's mother in law is an avid couponer/rebater, and saves good amounts of money doing it. Has it all organized in one room, I'm in awe of her determination and the work she puts into it.

She's made saving money a science!
Plus she gets lots of free stuff that way too, lots of other methods she uses to save money, get rebates, and get free stuff.
I won't put in that much time but I always buy house brands and save a lot that way.