Do not worry about transport. Hitch-hiking in Libya is better than anywhere else on the planet. etch hitched across Libya from Tunisia into Egypt in three days, and never had to wait for a ride. As a matter of fact, if I saw a truck coming towards me, I would hide from it, because I knew it would stop, and it was a slower ride than the next passenger car which would also stop and pick me up. I even had cars going the other way stop and see if I had changed my mind and wanted to go back the way I had come. Everyone who picked me up compelled me to have a meal with them, so one day I had four lunches. I got a ride for 400 km in a landrover full of policemen going to a conference, and a ride in a car full of Palestinians who were very anti American, and our discussion centered around "Why does America Help the Jews". Yes, I knew, and explained it to them so it made sense.
I couldn't spend any money in Libya. Then the one time I went into a store to buy a can-opener and some chinese canned apples, the owner gave me everything I put on the counter for free, wouldn't accept payment.
Men who gave me a ride assumed that I must be destitute, and sometimes tried to give me money. I allowed one guy to force a 5 dinar note on me, only because he was so persistent, and wouldn't take no for an answer, telling me I was insulting him by refusing.
Therefore I had more $ going out than coming in, which caused problems at the Egyptian border crossing. I wasn't very experienced at the time, having only been on the road for six weeks, so I showed the extra money and my currency declaration form to the crossing clerk. Mistake. He believed my story of where it had come from, but said "this is very irregular! You must go down the hall and speak with Mr. Hassan!"
So I went back down the hall, straight back out the Libyan door, walked 500 yards back into Libya, 100 yards out into the desert, and hid behind a bush for eight hours, until I was sure that the shifts had changed at the border post. Then I went through hiding the extra money, and all went well.
Leptis Magna is beautiful, but that is the only thing I saw which was worth walking across the street to see. By all means go to Egypt, but the trip through Libya is only worthwhile if you have no better route, or just go to meet the (male) population.