installing Postgres 8.3 on Mac

I'm having problems installing PostgreSQL on my Macbook. I had v. 8.4
running fine but found that PostGIS doesn't work with 8.4 so I took 8.4 off
(just dragged it to trash) and tried installing 8.3 from
http://www.kyngchaos.com/software:postgres

So I installed both PostgreSQL 8.3 and PostGIS 1.4, the installs apparently
were successful, but I don't know where they are! Where did they get
installed? How do I find them? How do I start PgAdmin III? The readme says
something about a usr/ directory but I can't find that? If I have to use a
terminal, what exactly do I need to type?

After a few hours of getting frustrated with that I tried another installer,
PostGres Plus http://www.enterprisedb.com/products/postgres_plus/download.dowhich
included PostGIS, this one seemed to be a better package but that
install failed, What gives?

I have GRASS and Quantum GIS both installed and working fine, I just need to
get this postgreSQL and PostGIS thing installed. Please anyone, some very
specific directions. I don't know much about macs or shells or terminals.

Why did that 8.4 install go so smooth and this one is horrible?

I have PostgreSQL and PostGIS working fine on my PC. I thought Macs were
supposed to be easy!

Help! Please!

Andy

--
Andrew Maracini, GISP/AICP
Superior GIS Solutions LLC

3309 N.Casaloma Dr. #114
Appleton, WI 54913

http://www.superiorgissolutions.com
920-574-2090
906-361-4132 (cell)