I thought it might be a good idea to compile some links to online resources which list cosmetic ingredients, just so they're in one place and easier to find

I've dug through my bookmarks and found these sites, if you have any others to add go right ahead!

Cosmetics Unmasked Ingredients List
This is a good list (about 6,000 ingredients they claim), but some of the information is not on the site (they want you to buy the book).

www.gina.antczak.btinternet.co.uk/CU/ING.HTM

Cosmetics Cop
A great list of ingredients including their effects.

www.cosmeticscop.com/learn/dictionary.asp?TYPE=MAIN

NuSkin
This site only lists ingredients which they use in their products, and most of them are "natural" and they seem to be a "network marketing" type company, but the ingredients list is fairly good and worth looking at if you can't find the ingredient anywhere else.

www.nuskin.com/corp/science/glossary.shtml

European Commission - Enterprise and Industry
A European Commission website which disseminates information on EU policies which affect business etc..,. They have a list of cosmetics ingredients and their function, this is mostly technical but has been of some use to me in the past. Note: This is a 2mb PDF file.

ec.europa.eu/enterprise/cosmetics/inci/inci_2006.pdf

Health Canada
Has a useful list of banned and restricted (in Canada) cosmetic ingredients.

www.hc-sc.gc.ca/cps-spc/person/cosmet/prohibited_e.html

Herbal Luxuries Ingredients Glossary
A useful glossary of natural ingredients. The descriptions of the ingredients and their benefits are quite good, but as we all know, not all natural ingredients are good for us and some are potent irritants. Notwithstanding, this is an excellent resource.

www.herballuxuries.com/ingredientslist.htm

The Cosmetic Ingredient Review
Setup by a cosmetic trade association with support from the FDA they independently review cosmetic ingredients safety. This link is to a PDF file which lists ingredients found safe, together with the concentration. Updated in December 2006.

www.cir-safety.org/staff_files/safeasused.pdf