I would like help in purchasing a fax modem that would work
well with Linux.

I checked around where I live: Calgary, Alberta, Canada.
I found a limited number of modems. There are a few software modems,
but I thought I would try to get a hardware modem if I was going
to purchase one to avoid problems with drivers. If these are
not suitable, can someone recommend some that I can order online?

This is the only ones I could find beside US Robotics:

Askey V1456VQH-T2 56k PCI fax/modem Hardware based, bare unit only
Condition: Used

Aopen FM56-PX V.92 Fax/Voice Modem
Quote:
Info:
- 56Kbps download speed from Internet
- ITU-V.92 and K56Flex Dual Standards
- Quick Connect
- Modem-on-Hold
- Upstream up to 48Kbps
- Telephone Answering Machine (TAM) and Voice Mail Operations
- 16550/A Compatible Enhanced UART for Sustained DTE Speed of
115,200bps
Specifications:
Model: FM56-PX
Solution: Conexant CX06834-11 single chip HOOVER V.92
Modem/Fax (Kbps): 56K / 14.4K
V.92: YES
ASVD: NO
Caller ID/TAM: YEX/YES
PnP: YES
Bus: PCI 2.2

I am also getting phone with Shawcable: digital phone. Is this a
problem with a fax modem?

Thanks