In Afghanistan, the Taliban are finding that their Medieval warrior mentality and physical hardiness are no match for smart bombs and even smarter intelligence work. The Taliban fighters are often described as clever and adaptive. They are. But the Taliban fighters, including many of the leaders, are illiterate and uncomfortable with new technology. They constantly get nailed using cell phones and walkie talkies (like the Motorola models available worldwide), even though it's common knowledge that the U.S. frequently eavesdrops. The Afghans believe the Americans are using some kind of pagan "magic", and if an Islamic warrior is pure-of-heart, the magic will not work. The better educated and more astute Taliban leaders (from wealthier families that send their sons to schools, sometimes even college) complain about this bitterly in captured communications.
The Taliban spend a lot of their time staying hidden. There are Afghan police, and civilians willing to provide information. The Taliban have to hide weapons and ammo, as well as caches of food. The hiding places are visited periodically, to add or remove material, or just to make sure someone else hasn't found the stuff and made off with it. Finding and looting these caches has long been a popular outdoor sport. The movements of these Taliban, going to add to a cache, or just check up, are often noted by U.S. troops. U.S. troops can find the caches with UAVs and scouts on the ground, who observe the traffic pattern in the hills, and put pieces of data together to locate where the stuff is hidden. It's this kind of detective work that is being used to find and destroy the small groups that make and place roadside bombs, or recruit, equip and use suicide bombers.
One of the reason for sending 35,000 more troops to Afghanistan is to make available more scouts and intelligence specialists to collect and analyze the foot traffic, and deduce who the bad guys are and where there stuff is. Many of these troops will have experience doing the same thing in Iraq. In some respects, these methods are easier to apply in Afghanistan, where most of the action is out in the countryside, where a few guys walking through the hills stand out to an unseen UAV or American scouts just waiting to see who comes by and where they are headed.