Congratulations on your upcoming wedding! I am in the same boat! We too are incorporating quite a bit of Chant for our Nuptial Mass. Providentially, a number of fantastic resources exist on the web. Also, stephraim is absolutely correct about the Propers of the Nuptial Mass - we are using several of them ourselves!
I also got in touch with the aforementioned Aristotle Esguerra, he was most helpful in getting me the music for the Propers.
Here are some other helpful links:
This website has music and recordings for all the settings of the Ordinary of the Mass (Kyrie, [Gloria,] Sanctus, Agnus Dei)
This website has links to untold numbers of hymns, chants, etc. - you name it, it’s somewhere around here.
Please PM me if you need/want further information, I am happy to share so you don’t have to find it all yourself!
Also - I assume the Mass will be OF, and (other than the Gregorian Chant) in the vernacular?