Never heard of .igc files, but Filext.com says they’re “Global Positioning System Datalogger” files…whatever that means. It’s also possible they’re proprietary file extensions from some software (Inscriber CG maybe?), which usually means only that software can use them. Regardless, you just need to find or buy the Rubino Sans font in the proper format and drop it in your system font folder. On Windows, the easiest is to get a True Type font (.ttf) and drop it in C:WINNTFonts (I’m on Win2K so path may vary depending on your O/S and drive configuration). When you close and reopen PS, the new font will appear in the list (not always in alphabetical order). Mac font folders can exist in several different places and I’ve yet to figure out which is right for new fonts.