Networking :: usb dsl modem problem

Hi Peeps
I've just installed dsl on an old toshiba portege and it's gone fine apart from a couple of problems, I'm using a speedtouch 330 dsl usb modem I've used this before with slackware and ubuntu without problems but on dsl I need pppoatm I'm also not too sure where to put the firmware any help gratefully excepted.
Pete