Mineral rights are very similar to surface real estate, just upside down. Just like real estate, the key is location, location, location. The most valuable mineral rights are where there are good reservoirs with the right parameters for successful production. The geology has to be right and there has to be enough pressure (either natural or artificial) to get the hydrocarbons out of the ground. And being close to transportation is also helpful.
The forum has a good link above as mentioned by Dusty1. Start there. Also go the oil and gas commission website for your state to see what resources are there. Some excellent books have been recommended on the forum. You can find them on the www.naro-us.org website, public websites and others are privately published.
Use the magnifying glass above and type in “books” or “recommended reading” and you will find quite a few links on the forum.