RTP (Research Triangle Park) has lots of employers. Their employment site has a list of all the companies in RTP with links to them.
Other major employers in the Triangle are the area's universities. NC State, UNC-Chapel Hill and Duke all have online job postings.
State and county government are also big employers in this area. State level government employment opportunities can be searched by county--(search in Wake, Durham, Orange, Johnston and Chatham Counties, which are all counties in the Triangle region).
County-level government employment opportunities can also be found online: