jkvon,
If it is a physical fax machine it would be connected to a Single Line port on the system.
Depending on the chassis you have there could be 2-4 built into the system.
There are additional SLC cards that can be added as well.
You should be able to sort your phones according to type by clicking at the top of the column.
If you are viewing it in the old legacy mode single line devices show up as a white telephone on the left hand side before the extension number.
Thanks,
TE