Latex & letter's headers...

[Vittorio <vdemart@supereva.it>]

Well, actually Latex isn't that easy, is it? Or, it's definetely the
easiest way of printing a rich and elegant book and report from
scratch and with the easiest, console editor...

Now, down to business! My problem is that I can write a letter with
latex but I cannot find the right commands to insert the official
colour logo of my firm (*.jpg,*.ps,*.pdf) into the header of the
letter and other chats in the footer.
 
I've been trying to look for a solution in the amazingly and
misleadingly wide Latex documentation but couldn't find anything
helpful.

Could you please help me (giving an example if possible).

Ciao

Vittorio