Here I keep some landscapes that I've made so that you won't have to edit the landscape(hills and lakes). There's a pic of every landscape on this page and if you click on it you'll se a larger pic.
To use the landscapes just download them into a temporary folder then unzip them to your stunts folder (i.e. C:\games\stunts\) then edit them as you would any normal track.
To be able to use them over and over you can save the finished track under a new name.