Tourism Authority of Thailand: Phetchabun Information - Tells of attractions, festivals, local products, and places to stay. Includes a map. - http://www.tourismthailand.org/destinationguide/list.aspx?provinceid=54
Wikipedia: Phetchabun Province - Tells a little of the geography and history of the province. - http://en.wikipedia.org/wiki/Phetchabun_Province