I stopped making labels awhile ago just because I don't feel it's worth the time, but I can see where you'd want to label them at a wedding. Adds a nice touch.
When I was labeling, I would spray polyurithane*sp?* over the labels once they were printed on removable label paper from onlinelabels.com It helps keep them from bleeding, but not to the level of commercial brews. You can buy water resistant ink and most office shops, but it's expensive.
It was once suggested to me to use an alternative to labels. Make little tags like something you'd see on a stuffed animal. Put them on a little dog tag like chain and drape it around the bottle neck. It adds a unique touch and it's easy.