I am an independent developer in Texas and had to wrangle with the Texas Comptroler over the States' Sales and Use Tax. Things are pretty obvious regarding resale (e.g., FileMaker software). But database consulting is a whole other matter. It used to be back in the 90's and before, that in Texas, Services were not taxed. So you have a lawyer provider services or a tax accountant, those "services" were not taxable. However, when I talk with the Comptroller, they want to put database consulting in a category called "Data Processing Services" (Title 34, Part 1, Chapter 3, Subchapter O, Rule §3.330) because it doesn't neatly fit anywhere else in their definitions and they won't categorize it as general consulting. This rule came out of the State trying to figure out in the 90's how to deal with Internet Service Providers and they determined they needed to tax users and eventually this came to include all Data Processing Services.
A similar type IT business is web development tied to a database. Here in Texas, web developers have been nailed by the Comptroller for not collecting taxes for creating web pages. You can read more about Rule 3.330 and Web Developers at http://keeptexas.org/blog/tom/understanding-texas-sales-tax-web-related-professional-services
One example the Comptroller gives is that creating a web page and providing server space is taxable. But consulting services are not. So is creating a FileMaker layout taxable? The Comptroller has told me yes several times even though quite a few developers tell me I don't have to. For now, I just am charging sales tax on development costs for projects in Texas. Of course that brings up a whole other topic of if I am developing here in Texas connectly remotely to a machine in another State, which State do I owe the tax too.
Personally, I think this is just government creep slowly working its way into taxing things it traditionally said it was not going to tax via wordsmithing.
Oh the fun of being a small FileMaker development company. But I would be interested on how other States are handling database consulting or other experiences with the Texas Comptroller.