It depends on the light bar you go with. I was all set to buy the brackets from kjdavis above as his look to be a terrific product; however, after receiving the lightbar, I realized that his bracket wouldn't work for me. My light bar didn't come with the bolts on the sides, so I couldn't mount them to his bracket.
Granted this is not a ridiculously overpriced LED lightbar from Rigid, but it is at least 8 times brighter than my brights! Here is the one I purchased: 20inch 126W CREE Spot Flood Combo LED Work Light Bar Offroad Truck Wagon 12600LM | eBay
If you buy this lightbar, then it will cost you a little over $5 to make your own bracket. I went to Home Depot and bought two of these: Everbilt 5 in. Zinc Plated Corner Brace-15212 at The Home Depot
I took my RotoZip and cut off about 1" from only one end on each brace (so now it's 5" x 4"). I then wrapped the exposed, cut edge with some electrical tape. Afterwards I used my RotoZip to widen the middle hole on the cut side (4" side) to fit the larger bolt that is included with the "mounting brackets" pictured with the lightbar on eBay. The non-cut side (5" side) bottom hole mounts directly to the bottom hole where the OEM fog light bracket used to be. Each bracket will only be mounted to the bumper with one bolt, but the cut edge (if measured correctly) rests against the inside edge of the bumper (hence the electrical tape for a buffer).
If you do this, your light will be positioned at the exact height and exactly flush with the front of the bumper with no vibration while driving. Using the supplied "brackets" from the lightbar company, all you have to do is center the light left to right and make sure it's aimed where you want it.
If these directions were confusing, I can take some pics tomorrow (I have some 6"x6" corner braces that I originally used before switching to the 5" that I can take some pics of).
Here is the outcome:
P.S. I never even took the bumper off.