Old Leitz/Marchioni Tiltalls offer the best bang for the buck in used tripods, in my opinion. They go for around $100 and include the head, are relatively compact and weigh about 6 lbs. They were made for 4x5". A new one is about the same price, but an old one in good condition is a better tripod.

For larger cameras or people needing a really tall tripod, Majestics are usually a good deal. If you get the extension legs and the combination geared column with the rapid column inside it, it goes up to at least 15 feet, and they have separate bubble levels for each leg, which is a great feature. The geared head is pretty heavy, but if you have the type where the head clamps onto a tube, you can get an adapter for it--still made--for a standard 3/8"-16 tripod head bolt.