Is there something to use to level a floor before ceramic tile is layed down. One side has the original wood floor and the other side has all the cabinets and is, linoleum on particle board and that looks like it was glued down to the original wood floor. When we do, put down the underlayment board on the wood floor side. The floor will be just off enough that is wont be even. Any help would be appriciated! Thanks

Hello Butler,
I'd like to help but I'll need more information please? Are you saying that you have hardwood flooring next to vinyl flooring and you plan to install tile to bridge both surfaces?
First, some basics. You will need to remove all layers down to the subfloor before you consider how to level everything up. Once the subfloor is cleared up and you've determined that it is indeed sturdy enough for the tile you plan to install, then you can begin to consider methods of leveling the floor to match any existing elevations.
Self-leveling compounds are very useful for this, and are relatively easy to use with careful preparation. Thinset mortars *can* be used to compensate for some minor elevation issues but should not be relied upon for bed over 3/8". Medium bed mortars can be used up to a thickness of 3/4", but you have to be very careful and confirm that the brand you are using allows for this. The best method of filling elevation changes is to apply a layer of plywood adequate to your needs, and then apply your underlayment over this in a continuous plane.
Best of luck,
Shaughnn

Thinset mortar should only be used to make up very subtle height differences. I would start at the subfloor level and level that out first.

True Hardwoods