I have just published my first pass at a .net wrapper for talking to the pager duty api. The source is on github and the package is up on  Here is a quick example of usage:

var svc = new PagerDutyAPI("yourpagerdutysubdomain","APIToken");

//Get all the alerts for the last 24 hours
var alerts = svc.GetAlerts(DateTime.Now.AddDays(-1),DateTime.Now,Filter.Unspecified);