Be careful asking these questions, it can lead to deal spotting chiclets.
Review the sellers on this list and browse on your own:
http://www.bladeforums.com/forums/entry.php/121-Who-are-the-Bladeforums-Paid-Dealers
A far as incentives, don't hold your breath. There are some coupon codes available at some retailers, but you don't get "special treatment" for ordering 3 knives, unless you personally know the dealer and call them a friend. If you bought the entire stock at a store, you might get incentives not for 3 knives though.