The word "lacking" means not having or being without something that is typically expected or desired. In the given context, it implies that the person is expressing regret or disappointment because they do not have showbiz magazines available.
Note: The provided meaning of the answer is for the latest New York Times crossword puzzle clue: With 40-Across, "Got any showbiz magazines?" "Regrettably, we're ...". Explanations are generated by AI and may be inaccurate.