you can find some apartment around the CAU(China Agricultral University), I moved to a professor's house the day before yesterday. It's a new house building, and the environment are very good. quiet and clean. Or you can also find in Huaqing Jiayuan which south to the east gate of Tsinghua University, and there always have many international standard apartment for renting, while prices are not cheap too. Anyway you have many chances to find a good house around Wudaokou, if you have no time finding it, just ask one house agency, they'll supply you soon, but they will charge for service fees.