Try a shop that has a membership where you get 10% back in store credit. GoPro sales are really rare, unless they're global sales that come prior to a new GoPro product launch. If there are sales, they need to be kept on the downlow, else the sale dies fast. GoPro is pretty strict on their pricing. I'd say eBay, but even prices on eBay aren't all that great.
I would say wait n see u til Sony can is more reviewed unless u need sooner vs later . It was recently released and we're finally seeing some real competition, which may lead to pricewar. I'm a camera geek and I'm waiting a bit.
It's not an online thing. Your local REI (because they have a liberal return policy) accumulates tons of returned stuff and every so often they have basically a yard sale to clear it out. Check with your local store but it can be anything from 15 year old shoes to go pro blacks.