If you have a Win32 workstation...
Look here:
http://sources.redhat.com/cygwin/
Then click on the thing that says "Install Now" (Looks like a black "C"
with a green tongue).
after a small boatload of clicks, you will see a Window labeled "Cygwin
Setup".
Under +All
you will find...
+Admin
+Archive
+Base
+Database
Click on the plus sign next to the Database category.
You will see:
7.2.1-1 [options] [Bin] [Src] [Package] posgresql: PostgreSQL
Data Base Management System
In other words, they already have an automated installation procedure
for PostgreSQL if you are using Cygwin.