Internet based database

I maintain an internet site. The host is linux based and uses postgres on
the server.
I wish to install a smallish database (of names and addresses +) on the
host, and allow it to be accessed over the internet (by a restricted number
of people).
I have the database working locally on a MS Access database, but would
expect to transfer it to a postgresql database on the server.
My question is: What is the method of operating such a database over the
internet? Do I write an application to use at home which sends postgress
queries to the server, or do I access the server-based postgres program
using HTML or some other method?
Can I write an application which runs on my home computer, but sees its
database file on a directory at the server? I will probably be using Delphi
7 or a public domain postgres application.

Any explanation would be appreciated, or possibly direct me to something I
can read in the net. I have looked, but everything seems either too
complicated or too simple.

Russell
rcrosser(at)netlink(dot)com(dot)au