Have you even tried to find this on your own? I just did a Google search and found 3810 hits. The first 10 would all work for an Oil & Gas state (like CO, NM, TX, WY). I'm not going to copy the URL in here because I don't want to endorse any of them. All will give you pretty good lat/long for the center of a section. None looked like they let you put in a Northing and Easting to get better than that (but I didn't dig in very deep). None of them looked like they would be too hard for a Petoleum Engineer to work out.
I've had to do this several times and its never been very hard.
David