I'm a Landman with more than 30 years of experience keeping records straight for clients and client companies.
I agree with Walter - congratulations, you may be looking at a pot of gold! And you are definitely off to a new adventure, with lots and lots to learn about!
You can review the records of the County Clerk for any county in Texas at their offices for free. Many County Clerk's Offices even have their records, or at least some of them, online. Their records are indexed by name, in both Direct and Reverse Indexes [Grantor, Seller, Lessor, Vendor, Mortgagor - Grantee, Buyer, Lessee, Vendee, Mortgagee].
There are also Title Plants (Record Rooms) maintained by various Title and Abstract Companies that Index the Counties Records by legal description, but most charge by the hour for you to use them.
Division Orders are considered privately held records, owned by the various companies operating wells. But copies of Mineral Tax Rolls are available for publc viewing at most County Appraisal District Offices. All Appraisal Districts will have Rolls where you can look up an individual's producing (taxable) mineral interests. Some will have a second set of Rolls where you can look up all the owners of a given well.
We subscribe to an online website called DrillingInfo that posts Mineral Tax Rolls for most, if not all, of the wells in Texas. It is a little expensive for individuals, but if your list is not too long I may be able to pull them up for you.
First, you need to sort out all of the papers by which property they effect. Sort them by County, then by Survey, then acreage call / legal description. If you don't already know how, you will need to learn how to read legal descriptions to do that.
Once you've done that, send me a list of the Counties and Surveys and I'll help you map out what properties you have interest in the best I can.
The next step will be to determine the nature of your interest and how much of it you own (I'll be happy to show you how). And then to determine whether each of the tracts are under production, under a lease or "open".
I'm not sure how to do it, but the Mineral Rights Forum apparently has a way for you to leave me private messages or send me proprietary information if you want.
Hope this helps -
Certified Professional Landman
Fort Worth, Texas