The latest issue of MWBG (issue 386, the Waterloo special) contains PDF models of La Haie Sainte and Hougoumont (downloadable from the Goodies page).
Both models are cleverly designed - the buildings are not 3D, but only give the impression of being so.
The La Haye Sainte model was the easiest of the two to put together, and the results is shown below. I printed out the pdf sheet as is, and put some 6mm Napoleonic figures next to it for a scale comparison. Quite neat.