Here are the camera controls I have found. You can use them with something on your cursor, wether it's while building or buying.
CTRL-S flattens the camera down.
CTRL-W tilts the camera up.
CTRL-A Camera left
CTRL-D Camera right
Also the keys A and D move the camera left and right.
W and S move the camera up and down.
In Sims3 Mode, hold down the mouse button to tilt camera up or down.
Edge Scrolling - will scroll up and down only in areas of the edge of the screen that do not contain a menu. If there is a white menu overlay on the edge, the scrolling won't work.