The short answer is, maybe. Okay, I know that’s not very helpful. The basic rule is you must collect and pay sales taxes on goods or services in the state you sell the product or provide the services. Since my client lives in Texas, they would owe sales tax for any sales where the customer is also located in Texas. Sales to out-of-state customers are not taxable in Texas.
But the days of "no sales tax" sales on the Internet are under attack in many states. This is especially true in New York and California, where Amazon is having a well-publicized battle over whether they should be required to collect sales tax (http://www.newrules.org/retail/rules/internet-sales-tax-fairness).
As a practical matter, there is no easy way for the states of California or New York to collect from the seller in Texas whose customer is in their state. That is why these states are going after Amazon and eBay to collect and pay the tax. They know that once they force them to cave in, they will have no choice but to force their users (or as they call them, affiliates) to pay the sales tax. So in the future, it appears my client will most likely end up collecting and paying sales tax on all sales in all states.
Like any good CPA, I need to add a disclaimer: Unfortunately, it is impossible to offer comprehensive tax info over the Internet, no matter how well researched or written. And remember, I love my readers but having me bookmarked on your computer doesn’t make you a client: before relying on any information given on this site, contact a tax professional to discuss your particular situation.