Here are links to the manuals I can find on HP's site:
HP 6S Manual:
http://www.hp.com/cposupport/manindex/hp6sscient30827_eng_man.html
HP 6S-solar Manual:
http://www.hp.com/cposupport/manindex/hp6ssolarc30831_eng_man.html
HP 10B Manual:
http://www.hp.com/cposupport/manindex/hp10bbusin20038_eng_man.html
HP 10BII Manual:
http://www.hp.com/cposupport/manindex/hp10biibus30834_eng_man.html
HP 12C Manual:
http://www.hp.com/cposupport/manindex/hp12cfinan20040_eng_man.html
HP 30S Manual:
http://www.hp.com/cposupport/manindex/hp30sscien30829_eng_man.html
HP 39G Manual:
http://www.hp.com/cposupport/manindex/hp39ggraph30819_eng_man.html
HP 40G Manual:
http://www.hp.com/cposupport/manindex/hp40ggraph30822_eng_man.html
By the way, HP used to have page listing all the PDF manuals and part numbers for the rest of the manuals. This was located at http://www.hp.com/calculators/techsupport/bm_manuals.html
However, it seems they have redesigned the calculators area on the web site and this page is gone. You can still see the page in Goolgle's cache but the PDFs on HP's site have been moved. Use the links in my previous message.
Good luck!