Evelyn,
If the font is available to the system, it will be available to Photoshop
(although Photoshop is more 'picky' about the quality of fonts than most
other applications).
The font may not display the name you are expecting and therefor may not be
in the position you ecpect in the font list.
The font may appear in a second alphabetically ordered list below the first
list. If this is the case the font may well have the wrong writingscript
description.