I think your regex question was answered quite well but I wanted to remind you of some other hairy boundary conditions:
A friend of mine lived in a duplex when he was in college and his address was "36 1/2 Garfield St." So if he lived on "4 1/2 MILE RD" his address would have been "36 1/2 4 1/2 MILE RD" -- YIPES!!!
Is there a "1/2 MILE RD"? A duplex there would have addresses like "36 1/2 1/2 MILE RD" -- Double YIPES!!!
What if someone builds a duplex on "MILES RD" What would your regex do with "36 1/2 MILES RD"? -- did i mention YIPES!!!
You probably only have a fixed number of records to process and my suggestions are irrelevant but trying to process addresses in general is very hard.