reporter: the locally-owned bookstore may seem like a thing of the past, but don't say that to eileen mcgervey. >> at least once or twice a day we get someone come in that says. i didn't even know you were here. i'm so glad you're here. now, i don't have to barnes and noble. >> reporter: for mcgervey and many small businesses around the country, there's a battle brewing between locally-owned bricks and mortar stores and online retailers. the issue: e-tailers without a physical presence in a state don't have to charge state sales taxes. >> i have to pay taxes on what i sell. and so if someone else is doing business in the state i'm not sure why they wouldn't have to pay taxes as well. >> reporter: for states, levying sales taxes could mean an additional $12 billion in new revenue each year. >> over the last few years where they had to cut so much of theim budgets and not wanting to raise taxes a lot of states realize this is a tax that is already in place, the tax is owed. people who buy, the residents who buy online owe the taxes. there is just not a way to collect it. >> reporter: in virginia