Hello, as far as I know german to english keyboard layout the only differences are on the alphabet section of the keyboard.
your F8 key should be same place as normal, although maybe in case it's a netbook you have to find the F8 written in blue ink on one of the other keys and to activate it you have to hold down Fn key.
If you're not sure still, can you make a picture, upload it to imageshack.us or similar and copy the forum link to here?