I got mine new for $160.68 from gohastings.com with a general 20% coupon, which I think was a pretty good deal. They have 20% coupons for used stuff all the time, but it's been a while since I've seen one that works on new stuff too. Might be something to keep your eye on, though.
I got it from Amazon for $125 on Black Friday. If I remember correctly Amazons normal price back then was $175. Shortly after they released every season on Netflix so I sold the set on eBay. I would rather have watched the blu-rays but am tight on cash right now.
If you aren't in a rush I'm sure it will be a gold box deal on amazon or someone else will have a deal on it. I doubt it will be $125 but maybe $150.