Arriving in the modern town of Luxor by plane, you skim down over fertile fields that green all year round. If you're lucky, you'll see a farmer or two, their traditional gallebeyas pulled up around their knees as they tend to a water-buffalo-drawn plow. It's a scene that hasn't changed much since the first European tourists started arriving here a century ago. They found the local population living amongst the millennia-old ruins of Theban temples that they referred to in Arabic as Al Uqsor -- "The Palaces" -- which in time became Luxor.
Today, because it contains many of the biggest and most famous of the ancient monuments, Luxor is the center of gravity of the cultural tourism industry in Egypt. Most of the big sites are now open to the public and have, on the whole, been developed in a way that keeps damage to delicate ancient paintings and stonework to a minimum. The main downside of all this tourism is that the local economy has become completely dependent on foreigners, and tourists are subject to a higher level of hassle from touts, drivers, and salesmen than anywhere else in the country. For this reason, I recommend even independent travelers take advantage of tour operators here. It is, of course, quite possible to go individually from site to site, but joining a group for a day tour of the necropoli of the west bank or the temples of the east, cuts the annoyances to a minimum and lets you concentrate on the breathtaking array of ancient wonders that awaits you here.
When planning your campaign of sightseeing, keep a couple of basic facts in mind. Remember that the temples are mostly on the east bank (where the sun rises), and that the necropoli are on the west (where it sets). This has to do with how the ancient Egyptians saw the world, but more important for present purposes, it may determine how you set out your schedule: You'll need to do a lot of walking to see the tombs of the west bank, whereas temples afford you more opportunities to sit down and take a break. The other thing to remember is that, especially in the summer months (May-Sept), Upper Egypt is hot. In fact, it can be very hot. When confronted with the cost of private, air-conditioned transport, think of how much more you'll enjoy seeing monuments if you've just had a cool 15-minute break in a comfortable van.