I quickly thumbed through my old MSAR. Almost every U.S. public institution was about 80% or greater in-state. Notable exceptions:
North Dakota (I guess because of low population or some kind of agreement with another state)
Michigan--81 residents taken compared to 86 non-residents in 2004-2005 (BTW they require Ivy League numbers)
Ohio State--145 in-state vs. 64 non-resident in 2004-2005 (still near 75%)
Oregon--46 in-state vs. 62 non-resident in 2004-2005 (agreements with Montana and Wyoming)
Penn State--61 in-state vs. 66 non-resident in 2004-2005
Utah--75 in-state vs. 26 non-resident in 2004-2005 (still near 80%)
Vermont--31 in-state vs. 67 non-resident in 2004-2005
all Virginia schools
West Virginia--64 in-state vs. 37 non-resident in 2004-2005
Sometimes schools that are trying to enhance or keep up their prestige are more likely to let others in at the higher tuition rate, but keep in mind that the odds of non-resident admission at all of the above schools were tougher by several fold. By and large, the school of interest takes an MCAT of X for residents and MCAT of X + 5-10 for a non-resident (so you are still a much better shot in your home state).
Of course the level is more even in the Caribbean or U.S. private schools. The more prestigious the private school, typically the higher non-resident portion (though tuition is level save for scholarships). The exception here is Baylor which is really a state school wolf in private school sheep's clothing. Texas is a huge state that can easily stock such a prestigious school with its own residents, and since it is subsidized by the state, they are required to take mostly Texas residents. They must be doing something right, though.
AAMC has a more recent MSAR that you can buy from them for something like $30. It has almost everything you need to know in it as far as statistics are concerned.
