LINQ SQL query to display the status of tracked computers

This is my existing LINQ SQL. At the moment it works, however the using the coalescing operator for null results on the "let" clauses make me feel like I'm violating some sort of unwritten rule. Is there a better way?

Also, as this is on a web server, I don't know if this should be set static or not. Methinks not. But how do I get around that? It winds up being bound to a GridView.

public static List<TrackingComputer> TrackingBoardPCsgroup(string groupName)
    {

        using (dbiemrDashboardDataContext db = new dbiemrDashboardDataContext())
        {

            var query =
     (from t in TrackingBoardPCs()
      where t.TrackingGroup == groupName
      join p in db.GetTable<tblTBHealthPing>() on t.ComputerAsset equals p.ComputerAsset
      into pingInfo
      join h in db.GetTable<tblTBHealthHeartbeat>() on t.ComputerAsset equals h.ComputerAsset
      into heartbeatInfo
      let p = pingInfo.OrderByDescending(p => p.HealthPingTime).DefaultIfEmpty().First() ?? new tblTBHealthPing() { ComputerAsset = "Not Found", HealthPingResult = false, HealthPingTime = DateTime.Now}
      let h = heartbeatInfo.OrderByDescending(p => p.HealthHeartbeatTime).DefaultIfEmpty().First() ?? new tblTBHealthHeartbeat(){ ComputerAsset = "Not Found", HealthCurrentUser = "Not Found", HealthCurrentWindow = "Not Found", HealthHeartbeatTime = DateTime.Now, HealthUptime = string.Empty}
      let tc = new TrackingComputer
      {
          ComputerName = t.ComputerAsset,
          IPAddress = t.ComputerIP,
          Location = t.Location,
          Pingable = p.HealthPingResult ?? false,
          PingTime = p.HealthPingTime ?? DateTime.Now.AddDays(-100),
          Username = h.HealthCurrentUser ?? "Not Found",
          CurrentWindow = h.HealthCurrentWindow ?? "Not Found",
          Uptime = h.HealthUptime ?? "Not Found",
          HeartbeatTime = h.HealthHeartbeatTime ?? DateTime.Now.AddDays(-100)
      }
      orderby tc.Pingable
      select tc).ToList<TrackingComputer>();



            return query;


        }


    }