Destination tourist website - Official website of Petra
National airline - Royal Jordanian
Airports - To and from airport transportation guide
Weather guide - Best time to visit the country
General information - CIA Factbook
If you like to plan your trip ahead and enjoy travelling on your own, this is probably the best travel guidebook that has all essential information about the destination, including descriptions of tourist sites, travel maps and routs, suggested accommodation and transportation options and much more.