How to use Python to interface with Web pages?

[Peter]

Any help would be appreciated :-)

I want to write an auction sniping tool in Python. I know Python, but
I know absolutely nothing about web pages, javascript etc i.e. I want
the program to automatically log me into my eBay account, access the
appropriate item, locate how many mins/seconds until the bid time ends
and then automatically place a bid at the last possible moment.

I can see the web-page source - it looks to be javascript (to my
untutored eye :-)).

But how do I enter data and "simulated" mouse presses on a web-page
that I have accessed via a Python program?

So where can I start to learn how to do this? Any books available? web
resources that show examples or offer tutorials?

I have (in the past) written some python to scoop data off web-sites
but I have never written anything that interactively interacts with
the web-page contents and don't know where to even start on this one.

Thanks for any help/pointers

Peter