Irina,
Try our WnetCard Modules. This product is specifically geared for VFP application. It will provide direct link to Paymentech Orbital Gateway. This direct link will allow you to avoid per transaction surcharges that you have to pay to use intermediate "Internet Payment Gateways" like Authorize.Net. The interface is procedural, very fast and simple. You can download complete development package from our Web site.
Joshua Zavelovich
Medasyst, Inc.
www.medasyst-software.com