The Mycenaean palaces (destroyed in the late Bronze Age collapse) are quite famous, but whatever happened to the Spartan Bronze Age palace complex? Sparta was central to the Trojan War, whatever form it may have taken historically, so it presumably had the same shared culture & forms. The other Mycenaean palaces were literally enormous fortresses leaving substantial remains. A quick google search brings up a few articles about possible sites but no real answers. Is there a theory as to why Spartas palace was so different, or hard to find, or simply so elusive?
No.
Archeological surveys indicate that during the Bronze Age Sparta, Amyklai (the "fifth village" of Sparta, which became incorporated into the polis at a later period), and several perioikic communities had been settled, but there is no evidence of any sort of palace. The Menelaion (believed by classical-era Spartans to have been the burial place of Helen and Menelaos, and later a temple for their cults) doesn't date until the 8th century B.C, some two centuries after the last Mycenaean palaces were sacked and burned. Homer's poems are, at the very least, not believed to have been an accurate depiction of Mycenaean Greece in any event.
Source: "An Archaeology of Ancient Sparta with Reference to Laconia and Messenia", William Cavanaugh, published in A Companion to Sparta, ed. Anton Powell