Regarding fax / modem capabilities, a quick opinion:
Don't rule out the Intel (now PureData) SatisFAXtion/400. Provides 14.4
datamodem and 14.4 fax. It's advantage lies in the fact that it has a
good onboard CPU and enough memory (and smarts) to perform sends and
receives without the tremendous hand-holding req'd of others. Runs
$300 - $400 and, yes, WinFAX et al support it.