How to change machine+machine name and ip-address in Debian?

["Magnus Ericson" <adaguru@telia.com>]

I am new to Linux and Debian and needs to find out how to change the name
(both machine and domain) and ip-address.

To install Debian over the internet I took my machine with me to the company
where I work and used a name/ip-address of a machine I temporarly
disconnected.

Now when I have taken the machine with me home I need to change the domain
name to what I use at home and the IP-address to one of the reserved ones
for local use (172.x.x.x etc) and preferably change the machine name to
something that follow the filosphy of my previous names of my home machines.

I have really tried finding something about this but so far nothing that
makes sence to a new user like me. I have seen "settrans" mentioned but
there is no documentation about this on my debian box...

All sugestions are very welcome!

Regards
Magnus