TheRetrofitSource Coupons?
#2
#4
A terribly advertised one. They'd get much better response by simply putting it on their website. The only ones they will actually advertise (and that are worth using) are the thanksgiving and maybe spring time coupons.
#6
Follow them on Facebook. They post all their sales, promotions and upcoming items there. I want to say there were at least 6 discount/sale events last year. I was able to get 20% off for a July 4th sale.