Haha, I read this thread earlier this morning and finally sat down a few minutes ago to draft a response and logged on to paste it in and see madeintheuk beat me to it but here goes anyway...
Chipmunks _love_ to take up a perch 2 or 3 feet off the ground and survey the area. They'll stay still sometimes for as much as 10 minutes. On the ground? It's as if someone is holding a lit match to their tails.
If you have such a location within view of a window in your home that you frequently pass by, you'll have their numbers in check in short order. For example, there is an old cherry stump outside my kitchen window. Many times I'll see one just chilling up there. Usually I have enough time to go grab my rifle, load a pellet, get the tripod, sneak into the back yard, deploy the tripod, settle my breathing, take aim, and grease the chipper off the top of the stump.
Two other pesting locations I frequent have a similarly popular "tree stump of death".
Scatter some bird seed, cracked corn, and black oil sunflower seeds in the general vicinity to bring them in.
And while a tree stump seems to be the gold standard, a stack of bricks or cinder blocks or lumber also makes an enticing watch tower.