combined psych/neuro programs: U of AZ, U of Miami, Indiana U, Tulane, U of Mass, NYU, Brown, West Virginia U.
you'd do a TY/prelim type of PGY1, and then 5 years for the officially sanctioned combined programs.
regarding combined programs: I had the pleasure to speak w/ Dr. Jeffery Cummings from UCLA (considered by many to be 'the godfather' of neuropsychiatry in the US). I asked him what he thought of the combined psych/neuro path, surprisingly enough he advised to do one or the other and then to subspecialize.
You can go psychiatry and then a 1-2 year fellowship in neuropsychiatry, or adult neurology and then a 1-2 year fellowship in behavioral/cognitive neurology. looks like you're looking at 6-7 years after medical school for the combined programs, the same or more than doing one or the other + 2 years of fellowship.
below is a link to the ABPN's website re certification for combined programs/residents:
http://www.abpn.com/certification/faqneurology.html#dual
as far as overlap b/w the two: i've heard estimates that ~40-50% of general adult neurology patients have psychiatric comorbidities. it's prolly true that many neurologists miss many of these diagnoses or are uncomfortable in addressing them. but neurologists and psychiatrists have fundamentally different approaches to patients and different skill sets, and with the huge growth in each field it'd be *very* hard to be excellent in both. the much ballyhooed notion of the convergence of these fields doesn't hold up to scrutiny in my mind: most of neurology is based on internal medicine principles of diagnosis and therapy of "organic" disease, while it seems that the fundamental principle of most of psychiatry is to exclude "organic" disease [not to say that psych disease is not biologically based]. also, the personalities that each field attracts seem to be quite different (or maybe it's the docs i've been exposed to).