I usually use Ultalabtests.com to order my own blood work, but it pays to comparison shop even at an individual test level.

Being familiar with what tests I need to run and what the acceptable ranges are, there is literally no reason for me to go through the doctor appointment firewall anymore.

Around/after Thanksgiving, many of the online test mongers discount tests heavily, so it's not a bad idea to stock up for the year on lab work orders, as they don't expire.

Most online providers give you the choice of labs to use.