Depending on the size of place you're looking for Zig Zag Towers can be nice. Lot's of western expats (Brits, French, German, American, Canadian) younger families etc.

The buildings have nice pools and gyms (not to mention gorgeous views of the Gulf). The prices may be a little high for your range but the rents are definitely falling right now in Doha. You can inquire re: renting and pricing here (click Lagoon Plaza):
http://www.darqatar.com/BookOnline.aspx

Good Luck!