Go here:
http://www.simtropolis.com/stex/index.cfm?id=4273
Download the BAT and put it in---> My Documents/Simcity 4/Plugins
For some BATs you need the Rush Hour, and by the way, always read the Readme File, because you'll find there which packs of textures do you need to use that BAT.
By the way, that is the Landmark version, you have the Plop version too.
If you have more problems, just post it...