standard schemas for addresses, others?

Are there any sites with 'standard schemas' for certain, repetitive database needs? For
example, addresses and their components. Does anyone have a schema for addresses that will
work for the USA *AND* internation addresses?

entities
----------
Countries
States
Counties
Cities
street addresess.
Postal Codes

Some rules:
-------------
A/ Do duplicate countries
B/ No duplicate states in Countries
(states seem only to exist in 'Federal' governments)
C/ No duplicate postal codes in Countries
D/ Duplicate cities are allowed in Countries,
and in the world.
E/ Duplicate cities are allowed in States.
F/ Cities can have multiple postal codes
G/ Postal codes are assigned to only one city.
H/ Postal codes are assigned to counties.
I/