What you are doing is defining a type of sedimentary rock as 'sandstone' even where the grains of sand/silica are glued together with calcium carbonate.
Sandstone glued together with silica is a tad different ~ if you've ever been to Wausau Wisconsin you'd see a ginormous outcropping of the stuff ~ a glacial movement during the last peak period transported much of that mountain to Northern Indiana and Ohio ~ we had a bunch of it in the backyard of the home where i grew up. That was not glued together with calcium carbonate. BTW, disturbingly, I've found some of the same rock here in Northern Virginia so that'd be a glacial period BEFORE the Appalachians rose ~ probably the Snowball Earth period ~ just thinking of the size of an 800 mile long glacial flow.
Back to OK, the three areas you identified as having limestone are simply areas where there is currently active mining, mostly for crushed rock. Over in Indiana that quality of stone is usually turned into portland cement. However, in commercial grades of building limestone, you are going to find that some fine grained early ~ pre-life ~ limestones look to have sand in them.
Looking over the OK soils maps ~ of interest to agriculturalists if not geologists ~ there doesn't seem to be a lot of wind blown loess like you find further North, but there are 'sand hills' ~ in places.
When I look at this map ~ http://tapestry.usgs.gov/ages/carboniferous.html - I see Pennsylvanian limestone, and then coal, in NAWTHAN OKLAHOMA! There are other limestones to the Souf!