With the purchase of a new iMac, Apple seems to be offering your choice of Mighty Mouse (Apple Mouse) or Magic Mouse with the option of adding a Magic Trackpad to the Magic Mouse. I have no interest in either of those mice, and would prefer to simply get a Magic Trackpad with my iMac, which is priced the same as a Magic Mouse. Would Apple Retail be able to set me up with this at a brick-and-mortar Apple Store?
The retail stores only sell the standard configurations of their products. When looking at the specs for "What's in the Box" for an iMac, it includes a Magic Mouse. They'd have to open up the box and take out the mouse while giving you the separately packaged Magic Trackpad.
You're best chance is getting the Magic Trackpad thrown in at a discount.