There is nothing wrong with having a vivid imagination, but if it preoccupies you and interferes with your making your life work better, then indeed seeing a therapist is a good idea....while you are setting that up, take the 3 day free trial at my new website and start working on some real issues...www.myvirtualshrink.com
I think seeing a psychotherapist could be a good idea.
The doctor usually says that when people day dream there is other stuff on their mind. Therapy would help sort through that stuff and help free up your time for other stuff.
You could try scanning through some of the older posts and check out some of the doctors comments. I personally have found them incredibly useful.
Sorry I don't know your answer but you arn't alone. I daydream a lot too. I don't know if mine is excessive but it entertains me. Also I catch myself talking to myself but I don't know why. Daydreaming is ok and all but to much daydreaming may interfear in other things you do. If you think this daydreaming thing is interupting your life or what you do than seeing a therapist isnt a bad idea.