I installed PostgreSQL via the graphical install on http://www.postgresql.org/download/macosx/
I see it in my applications and also have the psql terminal in my applicat
From the Postgres documentation page:
sudo mkdir -p /etc/paths.d && echo /Applications/Postgres.app/Contents/Versions/latest/bin | sudo tee /etc/paths.d/postgresapp
restart your terminal and you will have it in your path.