http://www.marketplacefairness.org/
It requires each state that wants to collect from foreign sellers to provide a uniform state-wide sales tax policy, a single organization in each state to handle registrations/filings/audits, and free tax compliance software. It also builds a mechanism to certify companies (like Avalara) to take care of internet sales tax for you, and relieves businesses of liability for mistakes if they use one of these companies to compute/file their taxes.