Most of the ones he buys new here in Poland, though, are in English.
Do you guys have language locale set to English and location set to UK/US? It might be the reason? In the worst case only subtitles and menus should be in polish.. I'm pretty sure Gears of War 2 didn't have polish voices...
anyways, it's usually possible to buy UK versions of games on allegro.pl
Taking into consideration that games are much cheaper in UK many people import games and sell them here.