A team sponsored by Wargaming.net lead by David Cundall who says he witnessed one such burial of planes, have been investigating a site that was thought to have up to 36 planes that were buried in crates near the end of the war. However, based on the evidence they have obtained recently, it seems there are no spitfires buried at this location, and no substantial evidence supporting any other location, possibly leading to the end of the hunt?
Over 20,000 Spitfires were made between 1938 and 1948, and cost around £12,000 each.
David Cundal has spent 17 years of his life and around $200,000 dollars hunting the Supermarine planes down; presumably evidence stating there are no planes to find, will not stop him searching.
Link to Original Source