I hope that the other post was able to provide a great deal of information.And, I hope that you made it safe if you traveled in April.
However, I thought I'd better write as well.I grew up in RisingSun, although having moved from the area when I was 14.It is a very small town (likely 600 or 700 people, but could have drastically changed), so for historical records, I am unsure.I would think that the local postmaster there (43457 zip code) might be able to guide you in the right direction (i.e., mayor, etc.) if any town records exist within.
Note that RisingSun strattles both Wood and Sandusky county.So, although the town itself is considered Wood, many residents actually reside in Sandusky county.Further, the name seems as if it has always been in question -- whether it is Rising Sun, Risingsun, or RisingSun.
There are a few cemetaries around town, most affliated with the local churches.You may want to try looking in an internet phone database for any Henry in the local area.The AC and exchange when I lived there was 419-457, although that might have changed/expanded.Because it is a largely farming community, many families have been there for years and likely may be able to help you.
Do you by chance have an address or time frame when your great grandmother lived there?The address may be a great start -- in case the the descendents of her neighbors still reside in the local area.