The pop-ups from this site are absolutely useless and annoying as all get-out. It took me forever to figure out how to turn it off. The website claims to show you how to uninstall their program, but when you go to uninstall it, you cannot find it. It is an add-on that must be disabled by clicking "Tools" then "Add-ons" and then "Extensions." From there, it can be disabled, but I only happened to stumble upon that after several frustrating days of dealing with it.
I would advise everyone to avoid PricePeep like the plague! Totally useless, utterly annoying, and I honestly don't know how I got it on my computer in the first place. I despise that website.