Direct flights are available into Fort St. John and Dawson Creek from Vancouver, Calgary and Edmonton. Vehicle rentals are available from local airports; make sure to reserve in advance.
By road, there are multiple points of entry to Northeast BC. From Vancouver and the Okanagan, expect a two-day drive via Highway 1 and 97. Coming from Edmonton and Grande Prairie? Highway 43 is an easy one-day straight shot; from Calgary, Highways 2 and 22 will connect you to the main artery heading west in a longer but scenic route.
Highway 16 in Northern BC will connect you to Prince George, then onto Highway 97 north. Make sure you have all-season tires and check road conditions before you embark.