Help with storing spatial (map coordinates) data?

Hi,

I have recently switched to PostgreSQL and had no problem bringing our
existing (my)SQL databases and data into the environment. I am now
extending the functionality of our databases and want to start storing
spatial information.

The information is made up of latitude and longitude coordinates that
define a point or location on the earth's surface. e.g. degrees, minutes
and seconds north/south and degrees, minutes and seconds east/west.

I have read up on custom data types (with input and output functions) in
the docs but am not sure if that is the best way to go. Can anyone point
me to a simple, workable implementation of storing and managing this
type of data or advise me on how to structure a series of fields that
could combine to the required string?

I am running postgreSQL 8.1.4 under WinXP Pro and currently evaluating
an X-Talk front end called Revolution for the GUI development and have
only some general experience with SQL.

Thanks in advance

John Tregea