The compressed PPD files on a local CUPS server are located in:
/usr/share/cups/model/
The used PPD files by CUPS server are located in:
/etc/cups/ppd
If your printer is on a remote CUPS server, you can easily download the PPD file to your client with
wget http://server_name_or_IP:631/printers/printer_queue_name>.ppd
example:
/usr/share/cups/model/ # ls -la
total 556
drwxr-xr-x 55 root root 4096 Aug 7 2015 .
drwxr-xr-x 10 root root 4096 Aug 7 2015 ..
lrwxrwxrwx 1 root root 9 Feb 22 2013 0-driverppds -> ../../ppd
drwxr-xr-x 2 root root 4096 Feb 22 2013 Alps
drwxr-xr-x 2 root root 4096 Feb 22 2013 Anitech
drwxr-xr-x 2 root root 4096 Feb 22 2013 Apollo
drwxr-xr-x 2 root root 4096 Feb 22 2013 Apple
drwxr-xr-x 2 root root 12288 Feb 22 2013 Brother
drwxr-xr-x 2 root root 4096 Feb 22 2013 CItoh
drwxr-xr-x 2 root root 12288 Feb 22 2013 Canon
drwxr-xr-x 2 root root 4096 Feb 22 2013 Citizen
drwxr-xr-x 2 root root 4096 Feb 22 2013 Compaq
drwxr-xr-x 2 root root 4096 Feb 22 2013 DEC
drwxr-xr-x 2 root root 4096 Feb 22 2013 Dell
drwxr-xr-x 2 root root 12288 Feb 22 2013 Epson
drwxr-xr-x 2 root root 4096 Feb 22 2013 Fujitsu
drwxr-xr-x 2 root root 4096 Feb 22 2013 Generic
drwxr-xr-x 2 root root 4096 Feb 22 2013 Genicom
drwxr-xr-x 2 root root 4096 Feb 22 2013 Gestetner
drwxr-xr-x 2 root root 28672 Feb 22 2013 HP
drwxr-xr-x 2 root root 4096 Feb 22 2013 Heidelberg
drwxr-xr-x 2 root root 4096 Feb 22 2013 Hitachi
drwxr-xr-x 2 root root 4096 Feb 22 2013 IBM
drwxr-xr-x 2 root root 4096 Feb 22 2013 Imagen
drwxr-xr-x 2 root root 4096 Feb 22 2013 Infotec
drwxr-xr-x 2 root root 4096 Feb 22 2013 KONICA_MINOLTA
drwxr-xr-x 2 root root 4096 Feb 22 2013 Kodak
drwxr-xr-x 2 root root 20480 Feb 22 2013 Kyocera
drwxr-xr-x 2 root root 4096 Feb 22 2013 Lanier
drwxr-xr-x 2 root root 4096 Feb 22 2013 Lexmark
drwxr-xr-x 2 root root 4096 Feb 22 2013 Minolta
drwxr-xr-x 2 root root 4096 Feb 22 2013 Minolta_QMS
drwxr-xr-x 2 root root 4096 Feb 22 2013 Mitsubishi
drwxr-xr-x 2 root root 4096 Feb 22 2013 NEC
drwxr-xr-x 2 root root 4096 Feb 22 2013 NRG
drwxr-xr-x 2 root root 4096 Feb 22 2013 Oce
drwxr-xr-x 2 root root 12288 Feb 22 2013 Oki
drwxr-xr-x 2 root root 4096 Feb 22 2013 Olivetti
drwxr-xr-x 2 root root 4096 Feb 22 2013 PCPI
-rw-r--r-- 1 root root 1511 Feb 14 2013 PDF.ppd.gz
drwxr-xr-x 2 root root 4096 Feb 22 2013 Panasonic
-rw-r--r-- 1 root root 2866 Feb 14 2013 Postscript-level1.ppd.gz
-rw-r--r-- 1 root root 2868 Feb 14 2013 Postscript-level2.ppd.gz
-rw-r--r-- 1 root root 1762 Feb 14 2013 Postscript.ppd.gz
drwxr-xr-x 2 root root 4096 Feb 22 2013 QMS
drwxr-xr-x 2 root root 4096 Feb 22 2013 Raven
drwxr-xr-x 2 root root 4096 Feb 22 2013 Ricoh
drwxr-xr-x 2 root root 12288 Feb 22 2013 Samsung
drwxr-xr-x 2 root root 4096 Feb 22 2013 Savin
drwxr-xr-x 2 root root 4096 Feb 22 2013 Seiko
drwxr-xr-x 2 root root 4096 Feb 22 2013 Sharp
drwxr-xr-x 2 root root 4096 Feb 22 2013 Star
drwxr-xr-x 2 root root 4096 Feb 22 2013 Tally
drwxr-xr-x 2 root root 4096 Feb 22 2013 Tektronix
drwxr-xr-x 2 root root 4096 Feb 22 2013 Toshiba
drwxr-xr-x 2 root root 4096 Feb 22 2013 Xante
drwxr-xr-x 2 root root 12288 Feb 22 2013 Xerox
-rw-r--r-- 1 root root 5247 Feb 14 2013 deskjet.ppd.gz
-rw-r--r-- 1 root root 3276 Feb 14 2013 dymo.ppd.gz
-rw-r--r-- 1 root root 2527 Feb 14 2013 epson24.ppd.gz
-rw-r--r-- 1 root root 2429 Feb 14 2013 epson9.ppd.gz
drwxr-xr-x 2 root root 94208 Feb 22 2013 gutenprint
-rw-r--r-- 1 root root 7732 Feb 14 2013 intelbar.ppd.gz
-rw-r--r-- 1 root root 5544 Feb 14 2013 laserjet.ppd.gz
drwxr-xr-x 18 root root 4096 Feb 22 2013 manufacturer-PPDs
-rw-r--r-- 1 root root 2570 Feb 14 2013 okidat24.ppd.gz
-rw-r--r-- 1 root root 2432 Feb 14 2013 okidata9.ppd.gz
drwxr-xr-x 12 root root 4096 Sep 12 2012 omni
-rw-r--r-- 1 root root 9644 Sep 12 2012 pxlcolor.ppd
-rw-r--r-- 1 root root 9452 Sep 12 2012 pxlmono.ppd
-rw-r--r-- 1 root root 2901 Feb 14 2013 stcolor.ppd.gz
-rw-r--r-- 1 root root 2915 Feb 14 2013 stcolor2.ppd.gz
-rw-r--r-- 1 root root 2905 Feb 14 2013 stphoto.ppd.gz
-rw-r--r-- 1 root root 2918 Feb 14 2013 stphoto2.ppd.gz
-rw-r--r-- 1 root root 18102 Feb 14 2013 zebra.ppd.gz
-rw-r--r-- 1 root root 9581 Feb 14 2013 zebracpl.ppd.gz
-rw-r--r-- 1 root root 8353 Feb 14 2013 zebraep1.ppd.gz
-rw-r--r-- 1 root root 8933 Feb 14 2013 zebraep2.ppd.gz
/usr/share/cups/model/ #
/etc/cups/ppd # ls -la
total 872
drwxr-xr-x 2 root lp 4096 Jul 29 11:26 ./
drwxrwxr-x 6 root lp 4096 Jul 28 16:10 ../
-rw-r--r-- 1 root root 145901 Jul 28 16:10 Printer-200.ppd
-rw-r--r-- 1 root root 314026 Aug 31 2015 Printer-201.ppd
-rw-r--r-- 1 root root 407565 Jul 6 12:06 Printer-203.ppd
/etc/cups/ppd #