SDF 10 at Ashland KY (DWU)
SDF 23 at Campbellsville KY (AAS)
SDF 4 at Somerset KY (SME)
SDF 24 at Maury County TN (MRC)
SDF 20 at Fayetteville TN (FYM)
SDF 18 at Tullahoma TN (THA)
The bulk of them that I have seen are located in Tennessee, Kentucky, and West Virginia. Approach plates are available online to members at AOPA and FltPlan.com. FltPlan is free to use, AOPA's plates are for members only.