You can go the semi professional do-it yourself route
HERE.
or
You can go the basic way by way of no equipment and just a Blu-ray disc with test patterns.
HERE
At first I went the cheap route and bought the disc and calibrated it. It's OK but I was a little OCD and wanted it spot-on so I bought the C3 METER WITH CALMAN 5 TUTORIAL.
My LG LED HDTV has a better picture than most of my friends that have Plasma TV's is because mine is calibrated to a near perfection.
Or
You could hire an ISF Technician to come out and calibrate it for around $400 for a couple of hours work.