TaxCloud is now integrated with PrestoStore, a hosted web store system. You can use TaxCloud to calculate sales tax by selecting a few options once you log into your PrestoStore account. In order to use TaxCloud with PrestoStore, you will need your TaxCloud API ID and Key (found in the Locations section of TaxCloud) and a USPS ID. Detailed instructions are available in the PrestoStore Help Center.
You can learn more about PrestoStore.com at http://www.prestostore.com.