title: Help with Repository(ies) method
body: <p>I am new to this repository lark, so some help is gratefully received.</p>
  
  <p>I am trying to design a method to have a central payment website for all our sites.
   The sites will populate a table that return a GUID. All the sites will pass the GUID across to the central payment site. The central payment site will look at the querystring and use the GUID to retrieve the details concerning the order and which site called it.
    I am trying to make it flexible, so the following 
  1) Different payment providers can be used at a given time (ie Paypal, Google Check) without major hassel
  2) Different DB(orm) layers can be used (we use subsonic at the moment, but could use LINQ etc)</p>
  
  <p>I am not sure how to implement this. Any suggestions?</p>
  
  <p>Thanks</p>
  
  <p>Podge</p>