The secret....40 years of doing this.Actually, I have Jackson County marriage records at home so I didn't look anywhere on the net after you told me he was in Jackson County. ButJackson County has a great website through Rootsweb (unless you are trying to contact the administrator, and she is hard to find).It has early marriage records and some fairly current ones.
The other info came from a census record and I have a subscription for that, but there are many census records on line as well.
You are unlucky with this couple because of the dates they were born.The 1880 census is a great census (and I have it on CDs), but then there is no census until 1900 and they weren't living at home on that one.Since they were born after 1880, not home in 1900, and married soon after, a marriage record was a lucky break.
I would post on the Barnes GenForum and try to get some help there.There are a lot of Barnes living in Jackson County in 1880 so someone is likely to be working on the families.
Now....this is a rumor, but might be worth checking.I was once told that the library in Newport had a census for that county for 1890.It is not listed on any census list that I have seen, and the person may have been mistaken, but it might be worth a phone call to find out.