while I just was at it today, I thought i put the links in here (hope this is the right place )
IPMS Stockholm - Urban Fredriksson's Color Reference Charts
http://web.archive.org/web/20021211072531/www.ipmsstockholm.org/colorcharts/colorcharts.asp
Model Paint Database
http://scalemodeldb.com/paint
The Ultimate Model Paint Conversion Chart
http://www.paint4models.com/index.html
Cybermodeler Online:
http://www.cybermodeler.com/resource6.shtml
Miniatures.de
http://www.miniatures.de/paints-model-colour.html
Kisekae World - Color Conversion Charts
http://www.kisekaeworld.com/resin/colorcharts
Miniature Wargaming - Vallejo Paints and Citadel Color Equivalents
http://www.miniaturewargaming.com/index.php/mwg/comments/vallejo_citadel_paints_comparison_guide/
Amorama - Vallejo Conversions for Tamiya & Humbrol
http://www.armorama.com/modules.php?op=modload&name=Sections&file=index&req=viewarticle&artid=279&page=1
Humbrol to FS, Model Master, Airfix
http://web.archive.org/web/20021208203811/www.hobbyguys.net/Hunbrol.htm
Model Makers Resource - Humbrol Equivalents to Citadel Colours
http://themodelmakersresource.co.uk/facts/facts017.html
Model Painting - a link to a buy-able software for paint comparison
http://www.paintassistant.com/index.html
IPMS Stockholm - Urban Fredriksson's Color Reference Charts
http://web.archive.org/web/20021211072531/www.ipmsstockholm.org/colorcharts/colorcharts.asp
Model Paint Database
http://scalemodeldb.com/paint
The Ultimate Model Paint Conversion Chart
http://www.paint4models.com/index.html
Cybermodeler Online:
http://www.cybermodeler.com/resource6.shtml
Miniatures.de
http://www.miniatures.de/paints-model-colour.html
Kisekae World - Color Conversion Charts
http://www.kisekaeworld.com/resin/colorcharts
Miniature Wargaming - Vallejo Paints and Citadel Color Equivalents
http://www.miniaturewargaming.com/index.php/mwg/comments/vallejo_citadel_paints_comparison_guide/
Amorama - Vallejo Conversions for Tamiya & Humbrol
http://www.armorama.com/modules.php?op=modload&name=Sections&file=index&req=viewarticle&artid=279&page=1
Humbrol to FS, Model Master, Airfix
http://web.archive.org/web/20021208203811/www.hobbyguys.net/Hunbrol.htm
Model Makers Resource - Humbrol Equivalents to Citadel Colours
http://themodelmakersresource.co.uk/facts/facts017.html
Model Painting - a link to a buy-able software for paint comparison
http://www.paintassistant.com/index.html