The "Ruby Breastplate" can be found here:
http://img.dailymail.co.uk/i/pix/2007/01_wk4/CamillaR2801_328x450.jpg
These are the sapphires:
Royal Jewels of the World Message Board: Re: Duchess of Cornwall tonight (Photo)
(courtesy of Boffer on RJOTWMB)
Both sets are from King Abdullah--he also gave her a parure of emeralds, but we haven't seen it yet.
Here is the Delhi Durbar Tiara that Camilla has worn:
http://image63.webshots.com/63/9/0/34/541590034wGPnyJ_ph.jpg
Actually, here is a link to a some great pics of Camilla in her jewels:
Cornwall
As for tiaras, HM Queen Elizabeth wears the Girls of Great Britain,
http://image62.webshots.com/62/1/1/92/542610192ITfVFD_fs.jpg
Grand Duchess Vladimir, and now the Oriental Circlet quite often.
Here is a link, same website, to a section on her jewels:
Tiara QEII
The site is up now, but sometimes it isn't--but it is worth the wait if its down. I love it. It's an addiction site for me!