Ha! We used to live in the country as well. Our kid's school actually had a Tractor Day every year...and yes they played 'She thinks my tractor's sexy'
Anyway, www.cowboom.com is legit -- just the clearance site for Bestbuy. It also has a fair amount of used/trade-in merchandise (iPhones, Tablets, etc) that BB takes in when they sell a new product. I've found some excellent deals there -- KNS8400s for $73, Aviators for $56, etc. Also, my local BB stores will match Cowboom's pricing (except Deal of the Day)...although some BBs apparently won't. Got my DT1350s for $174 at a local store that way.
I personally haven't bought from Buysonic. However, it's essentially Sonic Electronix's version of Cowboom. The deals I've seen are very good for the most part. Several long-term members have vouched for them and I'd have no problem pulling the trigger on a deal that interested me.