Nothing wrong with hunting for your own stuff, I do it myself; however I like to always have a supply of good knappable material on hand to turn to gravel or points.  If you want some Edwwards Plateau chert, go to Campwood, Tx , take highway 55 South toward Uvalde.  The highway crosses  the Nueces River about 5 or 6 miles south of Campwood.  You can pull off the highway and park under the bridge where you can load your car or truck down with all the chert you want.  A lot  of it is some of the nicest rootbeer you've ever seen.  Various other colors also occur.  Good luck and have fun.