Pretty much all online for me now because the closest B&M stores are further than I'm willing to go (I'm lazy, so let's say I won't go anywhere over 5 minutes away unless I NEED to, lol). Also, the local B&Ms don't really stock what I use/need anymore.
I DIY my juice, so that's online for the nic and flavorings.
Using a KFL+, so I just build my own coils at home and no longer need to buy them for my atomizer (I used a ProTank 2 Mini from the time that they were released until a few months ago - but I bought the coils online because they were about 1/2 the cost of the B&M store's prices).
I totally agree with 2pksAday as far as coupons, due diligence on prices, and avoiding fakes (although I prefer my KFL+ clone to my authentic).