You could buy one of the phone adapters that plug into wall jack and has 2 outlets on the other side, so you can plug the fax into one and the modem into the other.

I got another phone number with a distictive ring that I have my fax programmed for. It uses the same phone line, but rings differently. Only costs a $1 or $2 per month.

Thanks for the info! I didn't even know they made those outlets.

Yup, the phone company should be able to answer your questions. I asked for the distinctive ring option for my fax, with a different phone number. They obliged.