Hi TL. Looks like a good project. For grass in that scale, you can either use the 'scatter material', which is pre-dyed sawdust basically, or the grass 'mats', both of which will be available from model railway outlets, and most model shops. I'm not sure if they are still available, but Airfix used to do a set of about 40 figures, R.A.F. WW2 personnel. They are doing an airfield set at the moment, which includes a vehicle or two and a Nissen hut, and they also do a control tower.
If you can't find the figures, have a look at the Model Hobbies web site, under 1/72 scale aircraft, and military, you will probably find something suitable, as all of their products are illustrated. Just key in modelhobbies in Google, and it's the first one on the page.