Overhead door assemblies having both interlocking and releasable guide assemblies, and multi-piece guide track assemblies for use with same are disclosed herein. An overhead door track configured in accordance with one embodiment of the invention includes a first side portion formed from a first piece of material and a second side portion formed from a second piece of material. The first side portion has a first guide surface and a first retention surface. The second side portion has a second guide surface and a second retention surface. In one aspect of this embodiment, the first side portion is joined to the second side portion to define an open channel or gap region therebetween. The first and second guide surfaces extend from the gap region toward a first direction, and the first and second retention surfaces diverge from the gap region toward a second direction, opposite to the first direction. The first and second retention surfaces can be configured to movably retain a door guide member.