I use my LBS for the stuff I want to see and touch before I buy. I also use them for everything that I don't want to install or build up myself, like forks and such.
Once a year I put in a big order at Nashbar for routine maintenance items--tubes, chains, lube, brake pads, cables (but I get the housing at the LBS), Bike Lust, and so on.
Tires I order online as needed since no LBS in town stocks the ones I like.