Kremit, I'm assuming you're looking for jobs in the oil industry? In Kansas, most of those would be in the Southcentral part of the state, around Wichita. Although Wichita is Kansas' biggest city, it seems like what few CEG'ers we have live in the Kansas City/Topeka metro area, and I'm not aware of any CEG'ers elsewhere in the state. With the price of oil being what it is, I don't know if there is much drilling going on, and most of Kansas' oil fields are pretty well depleted after their 1930's heyday.
But in the Wichita area, KOCH Oil is a biggie, and there are several small independent oil drilling/speculating companies in Wichita. Most oil production in Kansas is in the Southcentral and Western parts of the state, and natural gas production is all in the far southwestern part of the state. If you're looking at refineries, you're looking at McPherson, Coffeyville, or ElDorado, all located in Southcentral or Southeastern Kansas.
Let me know if I can help ya with any more questions. I'm not directly in the oil business myself, but I have/had buds in the oil/refinery business and I grew up in the middle of the oil patch.