Joseph R. Reinhart has indexed the Louisville Anzeiger http://louisvilleanzeigerlisting.yolasite.com/listing-4.php
That is a great resource.
There are two Joseph Long's - one of them is age 22 died June 26, 1862. The death notice was put in the paper July 1, 1862. The other Joseph Long listed in that time frame died September 30, 1862, no age was given.
I did not see I did not see Florence Long in the index.