North Carolina
http://www.contractors-license.org/nc/nc.htm
North Carolina requires a general contractor’s license for jobs costing $30,000.00 or more.
License search, general contractor: http://www.nclbgc.net/lic_fr.html
License search, plumbing, heating, fire sprinklers: https://onlineweb.nclicensing.org/Lookup/LicenseLookup.aspx
License search, electrician: https://lookup.ncbeec.org/Lookup/LicenseLookup.aspx/