CrmDiscoveryService disco = new CrmDiscoveryService();
disco.Url = "https://YOUR.IFD.URL/MSCRMServices/2007/SPLA/CrmDiscoveryService.asmx";
RetrieveOrganizationsRequest orgRequest = new RetrieveOrganizationsRequest();
orgRequest.UserId = @"username";
orgRequest.Password = "password";
RetrieveOrganizationsResponse orgResponse = (RetrieveOrganizationsResponse)disco.Execute(orgRequest);
OrganizationDetail orgInfo = null;
foreach (OrganizationDetail orgdetail in orgResponse.OrganizationDetails)
{
   if (orgdetail.OrganizationName.Equals("OrgName"))
   {
   orgInfo = orgdetail;
   break;
   }
}
   if (orgInfo == null)
   {
         throw new Exception("The specified organization was not found.");
   }
RetrieveCrmTicketRequest ticketRequest = new RetrieveCrmTicketRequest();
ticketRequest.OrganizationName = orgInfo.OrganizationName;
ticketRequest.UserId = @"username";
ticketRequest.Password = "password";
RetrieveCrmTicketResponse ticketResponse = (RetrieveCrmTicketResponse)disco.Execute(ticketRequest);

CrmAuthenticationToken sdktoken = new CrmAuthenticationToken();
sdktoken.AuthenticationType = 2;
sdktoken.OrganizationName = orgInfo.OrganizationName;
sdktoken.CrmTicket = ticketResponse.CrmTicket;
CrmService service = new CrmService();
service.CrmAuthenticationTokenValue = sdktoken;
service.Url = orgInfo.CrmServiceUrl;