Doped LaMnO@sub 3@ yields the colossal magnetoresistance (CMR) family of perovskite materials. The physics is governed by competing interactions that include double exchange, super-exchange, Jahn-Teller effects, polarons, charge and spin ordering. To gain further insights, we have been exploring the properties of the related two-dimensional (2D) analogues that form a Ruddlesden-Popper series denoted SrO(LaMnO@sub 3@)@sub n@ where SrO barrier layers separate n-layers of Mn-containing oxygen octahedra. As in the perovskites, the La@super +3@ doped with Sr@super +2@ to yield the requisite mixed valent Mn@super +3@ and Mn@super +4@ needed for the CMR. We focus on n=2 (bilayers) and x=0.4 and 0.3, denoted SrO[(La@sub 1-x@Sr@sub x@)MnO@sub 3@)@sub 2@, which can be viewed as naturally occurring superlattices. They have reduced Curie temperatures relative to the 3D perovskites. Bulk single crystals grown in an optical image furnace are used. These structures are instructive because the competing interactions are now anisotropic. We illustrate examples of fascinating intrinsic and extrinsic behavior, including the intrinsic CMR values and the role of the extrinsic intergrowths on the magnetic properties. Intergrowths are stacking faults, such as occasional missing and/or extra octahedral layers. We find that intergrowths with extra octahedral layers can simulate 2D magnetic inclusions. Their magnetic and scaling properties provide a link to the 2D magnetism of artificially layered ultrathin ferromagnetic films. This work is supported by U.S. DOE BES-MS under contract #W-31-109-ENG-38.