Arizona appears to be sending "surveys" or "nexus questionnaires" to companies. The notice says they are conducting a survey of companies who have web-based sales within Arizona. They are looking for "some definite link, some minimum connection." Those terms are related to the Due Process Clause of the U.S. Constitution. It is the minimal threshold a company has to meet in order to have nexus. With that said, Due Process Clause nexus is not enough. A company must have "substantial nexus" as provided by the Commerce Clause of the U.S. Constitution.
The Notice mentions Arizona Transaction Privilege Tax Ruling 08-1. That ruling was issued on July 30, 2008. The ruling walks through how Arizona would determine if a remote retailer has nexus in Arizona.
Remote retailers would have substantial nexus in Arizona if they enter the state for any reason (solicitation, customer assistance, etc.). Internet retailers with affiliates in Arizona would also have nexus if the affiliates significantly assist the Internet retailer's ability to establish and maintain a market in Arizona. In the words of the Ruling, the affiliates must "enhance" the Internet retailer's Arizona sales.
If you or your client receives a similar notice from Arizona, please contact me for assistance in determining the appropriate response.