Sri Lankan organisations
Ministry of Foreign Affairs:  www.slmfa.gov.lk
Ministry of Finance:  www.fpd.gov.lk
Ceylon Chambers of Commerce:  www.chamber.lk 

Dutch organisations
EVD:  www.evd.nl
FMO:  www.fmo.nl
CBI:  www.cbi.nl or  www.cbi.cu

European Chambers of Commerce:  www.eccsl.com  

Looking for a Dutch manufacturer or trade company of a certain product you can search in some databases which are available on the internet. 
Holland exports:  www.hollandexports.com
ABC-D register:  www.abc-d.nl
Dutch yellow pages:  www.yellowpages.nl
Atradius Dutch State Business  www.dutchstatebusiness.nl