I've used the material of the link posted by HQ in a pair of WWII "weird" games using v2.2 set of rules...Mmmm if I remember well I oposted it myself in the "GM resources thread". I seemed to me a good source.
Caradhas, the idea of the British commandos is a good one for a RPG setting. I have some information at home, because I had the intention of do the same. Sadly it's all in Spanish, but, when at home, I can give you the original title of the book I used. As I suggestion, I would take in to consideration to begin your campaign in Norway. That was my original intention for the campaign, basically for some (in my opinion) suggestive reasons:
- There are good documented british raids in the occupied Norway, with excellent photographs.
- It's a ways to introduce the players in the first commando operation previous to the foundation of the SAS. So, they will be there from the very beggining.
- It's a good place for short, limited scenarios with novice commandos and it offers to you a nice contrast with the future operations in the desert.