[tex-live] updmap.cfg query

[Rowland McDonnell]

I want to add a local fount mapping file to my MacTeX 2008 distribution
by adding the following to a suitable updmap.cfg file:

=============================
# Rowland's stuff:
Map local_extras.map
=============================

I can find the following updmap.cfg files in texlive-2008:

/usr/local/texlive/2008/texmf/web2c/updmap.cfg
/usr/local/texlive/2008/texmf-config/web2c/updmap.cfg
/usr/local/texlive/2008/texmf-var/web2c/updmap.cfg

My questions are:

To which updmap.cfg should I make my addition?

Is it still right to run updmap.sys after making the above modification?

And how could I have found the answer to those two questions myself?

Thank you,
Rowland.