Sleep Issues....

I need serious help here. My little boy is 3 and he never sleeps thru the night. We have gone from sleeping on the couch, to sleeping on the floor, and sleeping in my bed. I did not like any of these options, but I do have to get up and go to work in the mornings. He does sleep in his toddler bed, but will get up at least once during the night. It can be up to three times a night. He really wants to get into my bed but we will not let him. So I just take him back to his room and he goes back to sleep. I feel like I have a newborn here? I have offerred prizes for sleeping all night. The latest phase is...he will not get up, but instead yell for me until I come to his room? I am sure someone else has this problem too. Any suggestions?