OK, so there’s not massive amounts of resources on this page, but what there is seems to have been useful to people!
First, you can always buy my little book for wedding couples which is published by SPCK. You can even get it in packs of ten!
Then if you have wedding couples who already have children, you might like to download and print out this: Wedding workbook for children
(for printing, print it two pages per page, back to back, in the order 8,1,2,7,6,3,4,5 if you want it too look like an 8 page A5 booklet)