Before I worked in a shop I used to drive out to Chapelhill and buy stuff from Performance. They always had everything at a good price.
That said, they sell Giant as we do, and advertised the TCR composite(ultegra) for $1800(regular price is around $2500). People were wanting us to price match so we called them up to confirm stock. Turns out they didn't have any and couldn't get any. It was just a teaser.
That said, buy stuff where you want just don't go into a local shop (any kind of shop) and bug them for info, get them to size you, fit you for a helmet, etc. if you just want to use this info to online buy.IMO, people that utilize this tactic should be whacked repeatedly in the shins with a cut down Yakima bar.