Here's a homemade scent killer recipe I pulled off the internet at the beginning our last season. I've used it religiously and I haven't heard a snort all year. I was directly downwind at ground level on several occasions and was never winded. I also took my archery deer and can credit this stuff. I had leather boots on and had walked all over the area looking for a tree (first time I hunted that particular tree). I missed this deer on the first shot and it proceeded to circle downwind of me, nose high in the air. He never caught wind and I ended up getting a second shot that took him.

1 gallon distilled water (or clean creek water, just no chlorines or iodines in it)
1/2 box of baking soda
16 oz peroxide
2 shot glasses of Hunters Specialty green liquid soap

Pour out enough water from a gallon jug to get the other stuff in and let it fizz for a while after mixing (about 1 hour or the top will pop off). Then just transfer to a spray bottle and you're set.

128 oz cost about $4.50 vs $8-$10 for 16-32oz of some other fancy kind.

Other guys have tried it as well and say they've had success. I won't hunt without it again.