Traxian Integrator is a free module that posts real-time order details in in an XML format. This enables easy order and customer integration with QuickBooks, using your free Traxian Network account (enabled by default). Free accounts support up to 10 transactions a month, with paid plans from $49/year. See link below for details.
Or, use this module to post XML orders to another system of your choice. Edit or deactivate at any time in Magento System Configuration (Traxian Integrator).
Your Traxian Network account can also enable QuickBooks integration of payments (e.g. Paypal, Authorize.net), invoicing, and other e-commerce transactions.
For more details on features and free/paid account options, see www.traxian.com/quickbooks_integration_magento.html
Update including various fixes relating to product attributes and account management.