Atascosa County Leases

I just received an offer from EOG for $500 per mineral acre/20% royalty. I have not determined what part of the county the tract is in. It involves the C Hernandez and Juan Ortiz Surveys (A-351 and A-652) I have 2 questions…who else has received any offers recently and what were the terms? 2. How do I determine the location of these surveys? THANKS