J.D.
My 4 year old was getting up a lot a few months ago. We started letting him keep his desk lamp on because the "monsters" were still around if it was just the little night light. Then, after he fell asleep we would turn off the desk lamp and just leave his night light on (so his sleep wasn't disturbed). We also used an incentive system. We have a regular calendar on the wall in his room. In the morning he could draw himself a smiley face for the previous day IF he didn't get up (except for an emergency or bathroom, of course). If he had 5 or more smiles he got a special treat that week -- discussed ahead of time and usually chosen by him from maybe three choices. Guess how many weeks he missed earning his prize? NOT ONE! His behavior was controlled so quickly by his own willpower. Also, we only had to use the chart for about 5-6 weeks and then he started to forget to do it and it gradually faded from use because the new behavior wasn't a big deal anymore to him.
Just a note about sleeping with him -- we did this a bunch of times out of desperation, and it did nothing in the long run to solve the problem. All it did was disturb everyone's sleep and make him less motivated to make it through the night. What kid wouldn't love the special time in bed with mom and dad? I know it's hard, but everyone involved will sleep better (in my opinion -- I'm not a co-sleeper mom, as you can tell) when your daughter gains that independence.
Good luck!