If it's an in-store only deal, I will go a few hours after opening and see if it's still available. Generally, it still is. I got the gold 3DS/ALBW bundle last year on Thanksgiving night, and the Xbox One MCC bundle this year late-morning on Black Friday. No hassle either time, just walked in, bought it and walked out. No lines, no fuss.
A mixture of both. I usually make my way out on Friday after the whole wave of insanity has subsided just to see if there are any diamonds left in the rough. You'd be surprised! Finding a deal online is pretty easy now given that we have Google, Nextag, Amazon, and multiple other websites that track and price match items.
I never bother with in-store sales. I just so-happened to be in a foreign small town on saturday so I nabbed some dog treats for my pets on a good deal but otherwise I just peruse online sales and bite if something catches my fancy.