You can get Medal of Honor 10th Aniversary edition for like £8 which has Allied Assault, plus two expansions, and Pacific Assault and Airborne. Just finished Airborne the other day, good game, not as good as Allied Assult, but good play through.
WW2 games I play/played:
Medal of Honor: Allied Assault
Medal of Honor: Allied Assault - Spearhead
Medal of Honor: Allied Assault - Breakthrough
Medal of Honor: Airbourne
Call of Duty
Call of Duty: United Offensive
Call of Duty 2
Call of Duty: World At War
Battlefield 1942
Battlefield 1942: Road To Rome
Battlefield 1942: Secret Weapons of WWII
Return to Castle Wolfenstein
Wolfenstein
Day of Defeat
Day of Defeat Source
Brothers in Arms: Road to Hill 30
Brothers in Arms: Earned in Blood
Brothers in Arms: Hell's Highway
Red Orchestra
Red Orchestra 2