I don't know if it's been posted before but this is for those who don't know:
Riot Girl Tristana (Like the league facebook page)
Free Riot Girl Tristana - EUNE
Unchained Alistar (Subscribe to Riot Games on youtube)
http://youtube.eune.leagueoflegends.com/en/youtube/
Dreadnought Garen (Follow them on twitter)
Free Dreadknight Garen - EU
These are all safe websites hosted by riot themselves.