To build a connection between your Windows Phone 7 accelerometer and Windows 7 device, you need to:
• Make dummy software to carry out signals from the Windows Phone 7 and Accelerometer to Windows 7. For writing a sensor driver in Windows 7, you will require UDMF (User Mode Driver Framework)
• Now move the Windows Phone 7 sensor data into Windows 7 PC by using Windows Communication Foundation (WCF) service on the desktop. This will allow Windows Phone 7 to keep working in sync with Accelerometer data. To keep the data moving from one device to another you need to run WCF service continuously.
Once you have established the connection you will be able use Windows Communication Foundation (WCF) to get the Accelerometer data by using the API sensors of your Windows Phone 7.