• Yudkowsky, Reductionism sequence (2008)
• Ladyman et al., Every Thing Must Go: Metaphysics Naturalized (2007)
• Bickle, Philosophy and Neuroscience: A Ruthlessly Reductive Account (2003)
• Bickle, 'Real Reduction in Real Neuroscience' (2008)
• Glimcher, Foundations of Neuroeconomic Analysis (2010)
• Ney, 'Reductionism' [for Internet Encyclopedia of Philosophy] (2008)
• Hohwy & Kallestrup (eds.), Being Reduced (2008)
• Drescher, Good and Real (2006)

I can't endorse everything in all these works, but they each provide insights into understanding reduction.

What else do ya'll recommend?