Planning where you want to go and what you want to see is essential if you are taking any sort of individual tour in Libya. If you're happy to take a set tour, you don't have to think about this, the itinerary will be laid out clearly and you go where they go. If you want any sort of tailor-made tour however you must make sure everywhere you want to go is included in the itinerary given on your visa application.
Your visa allows you to visit only the sites specified before arrival so it is really important to understand that you must specify the exact cities and sites you wish to visit before you arrive in the country. Once the itinerary is set you cannot make changes to it - in other words, you can't decide you'll give Tocra and Ptolemais a miss and use the time to go to Tobruk instead if Tobruk is not on your original itinerary, nor can you decide you'd rather go to into the desert instead of the cities of Cyrenaica.
You must do your homework, decide on the places you want to visit and confirm the itinerary before you apply for your visa as it cannot be changed later. Your travel agent will be happy to help you plan your trip to ensure you get the tour you want. Ad hoc stops along the way are fine and once you're at a site or in a town you can do what you like whilst you're there, but what you cannot do is change the overall plan.
Unless you're coming by sea, travelling between Tripoli to Benghazi involves either a 1000 km drive across the desert or flying. You may hear a tale or two about poor safety standards and old planes and there's no denying Libyan airlines were once something to approach with caution. As with so much else in Libya, things have changed in the last couple of years and the situation is much improved. The arrival of a new, privately owned airline, al Buraq, in competition with Libya's national carrier has seen a sharp rise in both service and standards.
There are several flights a day operated by al Buraq and Libya National Airlines. We took Buraq's 1830 flight from Tripoli to Benghazi, and the 1430 flight back to Tripoli at the end of our time in Cyrenaica. Both flights - in a new, late model 737 - were absolutely fine, with punctual departures and arrivals, clean and comfortable planes with plenty of leg room and efficient crews. The flight takes about 1 1/2 hours.
Checking in at Tripoli airport is another matter. This is where your travel companion really comes into his own - what signs there are are all in Arabic, so unless you can read it, you'll be lost. You need to get there early - 2 hours before the flight. Internal flights used to leave from a seperate terminal but at present they are sharing space with the International Terminal as a new complex is being built. In the meantinme, controlled chaos appears to be the order of the day. Seat allocations are fairly new concept it seems, and not everyone has quite grasped the idea, though it is catching on. Benghazi Airport was a doddle after that, though we did have to face more chaos when it came to luggage collection time at the other end. All I can say is watch out for determined ...... tourists who will move heaven and earth to ensure they get their bags first.