When possible, use a digital camera to take your photos.     In some areas, Kinko's will rent digital cameras. 

Try to include lots of color in your shot.   Avoid shadows!!  They look awful when digitized and viewed online.  They look even worse when scanned from a photo. 

When taking indoor photos try to use lots of natural light (light bulbs will put a yellow cast on your photo.)

Windows are great features to include in your photos, but they really mess with the exposure of your picture.  Try to keep them off to the side.  Avoid taking a picture directly at a window during daylight hours.  Your window will turn out normal, and the rest of the room will look like a dark cave.

Use a wide angle lens or wide format camera for interior pictures.