Connecting a orange wireless livebox

Hi,
I have a wireless orange livebox think its a inventel make. And a
belkin ADSL with wireless router Model No: F5D7630-4A. The livebox is
downstairs connected to the phone line and the belkin router is
upstairs. What I want to do is connect the belkin router wirelessly to
the Livebox and then connect a printer & 2 computers via a wired
connection to the belkin router.

I know I can connect the belkin router by ethernet cable and it works
but I cant do this,I have seen signal amplifiers which have LAN ports
on them but would I be able to use one of these to connect to a
printer or other computer?

Thanks for any help
Olly