Where can I buy a mountain bike?
check out @Wolfi's Bike Shop . It is located on Sheikh Zayed Road and they have a great selection of mountain bikes there.
Where can I buy the best set of headphones?
@Virgin Megastore it is located in many shopping malls throughout Dubai
Where can I find a café?
@Filli Cafe كافيه فيلي it is a great hangout spot where you can relax with your friends.
Where can I spend my valentines day?
@Jumeirah Beach Park AND/OR the fountain area outside @Dubai Mall facing the tallest building in the world, Burj Khalifa.
Where can I learn indoor sports?
@the India Club in Oud Metha near Indian High School. Has indoor sports facilities like Squash, Table tennis and Soccer.
Where can I find a maid?
@maidsindubai.com/. Check out this site. They are generally a bit expensive but if you live in an apartment, you could ask the maintenance people of your building if they want a part time job.