I have some data for Dutch airports. These are numbers from 2006 and the source is very reliable: the official statistics bureau of The Netherlands.
http://statline.cbs.nl/StatWeb/table.asp?STB=T&LA=nl&DM=SLNL&PA=37570hvv&D1=a&HDR=G2,G1,G3Passenger numbers:
Amsterdam: 45,988,966
Rotterdam: 1,037,971
Eindhoven: 1,170,521
Maastricht: 270,086
Groningen: 129,012
Cargo:
http://statline.cbs.nl/StatWeb/table.asp?STB=T&LA=nl&DM=SLNL&PA=37798hvv&D1=a&HDR=G2,G1,G3Amsterdam: 1,526,552
Rotterdam: 15
Eindhoven: 571
Maastricht: 54,152
Groningen: 16
