In most cases you will need a new Roof rack in order to have a light bar/lights.
There was a T4R member that did screw lights into his factory crossbars and it looked pretty good.
In terms of Racks Baja is probably the cheapest for a full rack. Perkins and gobi are more expensive but fit the roof lines better IMO.
In terms of Lights I would recommend the Rigid LED Bars. They are expensive but worth it.
Heres my truck with the Perkins performance rack and Rigid LED Light bar.