I have digital camera PENTAX Optio e10.how to take night pictures?i have tryed and they come out blurry. HELP!

Stay within the useable range of the flash.
As was said before, use a tripod or stabilize the camera.

Night shots are difficult. Forget trying to get a good picture at some sporting event or situations with a lot of motion.

Practice. Try taking pictures in your house w/ minimal light. Go to the front porch/deck whereever and play w/ the different modes on your camera.

Tripod.
or sit it on a table. the shutter speed needed for low light is too slow for hand-held photography.

Also- I find that night shots typically look better with some negative exposure compensation. You want night to look dark, cause it is.

A tripod is an absolute necessity. Also you can limit the camera movement by using the timer setting so that you are not even touching the camera when it starts to expose. You will need a windless night as well.. camera shake for long shutter speeds is the most probable cause of your blurry results.