Some problem with Linux SuSE10 - winXP networking!! plz help !!!

hi all !!!
i am a new comer in linux field ..
i need some help abt the following,


i have 3 computers in network ..
one with Linux SuSE (10.0)and windows XP(both) ,
and other 2 computers with windows XP installed.
( connected via switch / hub )


1) I have a ADSL broadband connection ( USB modem )
presently connected with one computer with Win XP.
I want to use this connection on PC with linux.
plz tell me how to setup an ADSL braodband connection in SuSE
linux?? (plz tell me the things in detail )


2) i want to share this connection with the other two computers
(which are working on windows XP).. if this kind of linux-windows
net connection sharing is possible , plz tell me how to do so !!


plz help me abt it !!!!


Regards,
UDAYAN