Bath Tub Problems?

My bath tub drain keeps on spewing out water. The water eventually fulls the whole tub and I have to scoop it up and pour it in the toilet. When i use the bathroom sink or the kitchen sink the water a pears there. I don't know what to do. Should i buy a snake or call a plumber? I don't want to use chemicals.Bath Tub Problems?
Just an extra little FYI - I used a snake (or rather, my husband did) on our toilet and it left lots of silver marks in the bowl. Nothing I did got them out until I used Barkeepers Friend - it's like Comet cleanser. It's wonderful for those kind of problems.Bath Tub Problems?
Finding the location of a blockage of this type is easy. Your plumbing has an outlet to take all the waste water out of the house. Each fixture connects to this system in series. You will have at least one cleanout before it goes to the street/septic tank. The blockage is somewhere between the fixtures that work and the fixtures that don't. The tub is the first to backup because it is the lowest drain. Find the nearest cleanout to the blockage and run a snake from the cleanout to the blockage. Have water in the tub when you do this so you can see if you are having any effect. You can also snake the line from under most sinks, just drop the traps. An inexpensive 25' snake should be adequate. Good luck.
It sounds as if you have a blockage in the pipe.Have you tried a Plunger? Or sticking some number eight wire down the drain?If this fails call the plumber.
If its backing up that bad you need to call a plumber.