I buy mostly online these days, and I have found that backcountry.com/steepand cheap.com/et al is the best place.

I have a pair of Keen boots that I basically lived in last winter. I notice that they are no longer waterproof. Had I bought them through backcountry, I would be able to return them and either have my full money refund (they're cheaper than what I paid for), or give me a new pair and give the rest of the money back.

Where else can you get that kind of service these days? Well, maybe REI or MEC in Canada, but I'm just kicking myself now I didn't buy from them.