Oh, it's an emanation from a penumbra.
Actually, there are 7 states with no state income tax: Alaska, Florida, Nevada, South Dakota, Texas, Washington and Wyoming.
The collection of state revenue through sales tax rather than income tax is exactly the same model as the Fair Tax model for the federal government to collect revenue through sales tax rather than income tax.
"Could you point me to the part of the Texas Tax Code where the Fair Tax model is being used? I can't find it in the nearly 300 pages that I've checked so far."
You're wasting your time if you expect the Texas tax code (here... http://www.capitol.state.tx.us/statutes/tx.toc.htm) to explicitly mention the FT. No state tax code explicitly mentions it as far as I know. But that doesn't mean it isn't using the same model, as I explained above.
Here is a list of the state income tax rates for all states...
http://www.taxadmin.org/FTA/rate/ind_inc.html
You'll see Texas has no state income tax. By definition this is the same model used in the Fair Tax.
If you do not support the FT, what tax reform do you support?