You can start by doing a search for "chert in {whatever state}" on line. You will likley find several geologic paper with the word chert. Most of these will only have some passing mention of chert, because no one paying for a geologic study is looking for chert, no economic value. Then the detective work starts. Look up that paper's references. Eventually you'll find someone who somewhere actually says where the chert is located. Problem is the study may be from the 1930s or something, and reference roads or landmarks that no longer exist, so you have to find old county maps that may show the landmarks, or interpret where the location is using modern landmarks and roads. Then you start searching at those locations to see if you can actually find the outcropping. I've been interested in geology since college and actually like the whole 'hunt' part myself. I have a construction-type orange/yellow vest that says "GEOLOGIST" across the back in big letters, if I wear that when I'm in the field no one ever asks me what I'm doing. (Still don't go on land posted No Trespassing.) Also look for the mention of chalk, since chert and flint are often found in chalk deposits.
I see you're in NC, so I'll save you a bit of trouble as far as searching in NC. Flint and chert are rare in NC, very few outcroppings of note, one now buried by a road in RTP. That reference was from a small mention in a college field trip report from the 60s, none of the current roads are in the same location as those mentioned in the original paper, I was pretty bummed when I finally figured out where it should be and it turned out to be under 4 lanes of concrete.
The others are minor and located in the Durham Triassic Basin. I have found some chalk which was just having a subdivision built on it, and I found only small chunks of poor quality chert. There should be another near the US 1 cut through southern Wake county, but I haven't found that one yet.
For flint and steel 'flint', the Uwharrie mountains in Uwharrie National Forest is where you need to go. The tops of Shingle Trap and Wolf mountains are covered by rhyolite, which is not actually related to flint but is what the NDNs of the state used as 'flint'. It makes really good flint and steel flint, but is hard to knap into any specific shape (although they made arrowheads and other things out of it.)