Certified LEGO Professionals (for instance) are allowed to buy in bulk from LEGO at reduced prices. You can buy lots of LEGO through the Pick-A-Brick program online, although this is prohibitively expensive, and they reserve the right to put a stop to any orders beyond a certain size (though they rarely if ever do this, since nobody I know of orders bulk this way). read more
Here, you can search for bricks and elements by specific details. Search by Brick Name If you know the name of a specific LEGO brick or element (for example, Brick 1X2) or part of the name (for example, 1X2), type it into the Brick Name field and click the blue button to display a list of all bricks that match your description. read more