Here are some links that I should've posted a long time ago. Sure, they're all in Japanese, but there's enough English in the menus to navigate to see pictures.
This is an overview site:
http://www.sti.jp/product/previousmodel/index.html
Blitzen 2001
http://www.sti.jp/blitzen/
Blitzen 2002 (for some reason, the flash version doesn't work anymore)
http://www.sti.jp/blitzen2002/no_flash/index.htm
Blitzen6
http://www.sti.jp/blitzen6/
Blitzen 2003
http://www.sti.jp/blitzen2003/
'02 LEGACY S401 STI version
http://www.sti.jp/s401/
'05 LEGACY tuned by STI
http://www.sti.jp/LEGACY/
'06 LEGACY tuned by STI
http://www.sti.jp/legacytunedbysti/
'07 LEGACY tuned by STI
http://www.sti.jp/legacytunedbysti2007/
'08 S402
http://www.sti.jp/s402/
'10 LEGACY tS
http://www.sti.jp/product/ts/
'12 LEGACY tS
http://www.sti.jp/product/legacyts/
'01 FORESTER STI II Type M
http://www.sti.jp/typeM/main.html
'09 EXIGA 2.0GT tuned by STI
http://www.sti.jp/product/exiga/
'12 EXIGA tS
http://www.sti.jp/product/exigats/
'98 IMPREZA 22B STI version
http://www.sti.jp/product/22b/
'00 IMPREZA S201 STI version
http://www.sti.jp/product/s201
IMPREZA WRX STI Prodrive Style
http://www.sti.jp/sti_prodrive/
'02 IMPREZA S202 STI version
http://www.sti.jp/s202/
'04 IMPREZA WRX STi spec C TYPE RA
http://www.sti.jp/spec_c_RA/index.html
'04 IMPREZA S203
http://www.sti.jp/s203/
'05 IMPREZA WRX STi spec C TYPE RA
http://www.sti.jp/spec_c_RA2005/index.html
'05 S204
http://www.sti.jp/s204/
'06 IMPREZA WRX STI spec C Type RA-R
http://www.sti.jp/ra-r/
'08 IMPREZA WRX STI ?STI 20th ANNIVERSARY?
http://www.sti.jp/sti20th/
'10 R205
http://www.sti.jp/product/r205/
'11 S206
http://www.sti.jp/product/s206/
'13 WRX STI tS TYPE RA
http://www.sti.jp/product/wrxstitstypera/
'13 BRX tS
http://www.sti.jp/product/brzts/