Text Coordinates?

I don't know anything about what your requirements are, what will work or won't work, but here's an idea.

You can place guides in photoshop precisely at specific X,Y locations (View|New Guide...). If you have Snap To Guides enabled, you can snap your text to the intercept of the guides. If you do it a lot, you can create Actions to automatically place the guides at specifc locations.

You can also use the character pallet in the options bar (when using the text tool) to control almost all characteristics of your text.

In addtion, note that you can use the Measure tool to help place guides precisely as well. The measure tool inherits the units (pixels, inches, cm, etc.) of your image. So right clicking on the ruler you can change the units and use your measure tool to help. I'm not suggesting the measure tool as a primary mechanism, but as a technique to help tweak when necessary.

That's about all I can come up with <shrug>.

Peace,
Tony