I discovered this site while fooling around on the internet. (How else?) Black Friday.com. They curate holiday ads. As I write this you can search 62 Sales, 22 ad circulars, and 8 Cyber Monday sales from one place, and most of the major retailers appear to be present.
(And even if they don’t have a sale ad for it, the search could pull up something on Google that’s just what you were looking for; I just used it to find something I was told would be hard to find in about 10 seconds, and saved 30 bucks on it to boot. It will be here in a few days.)
Love me some internet shopping. Oh, and they have a mobile app as well.