How do you get started on preserving a cemetery in the state of Illinois? Based on information obtained from the Illinois Historic Preservation Agency (IHPA), here's what I've found.
First off, research is important. You need to determine the ownership of the cemetery in order to seek permission. Your best bet probably would be to first, contact the owner to gain access to the cemetery to do further research and analysis, if you have not already done so.
Once you have gained access to the cemetery, take an inventory of the cemetery's features, including markers, fences/gates, paths/roads, etc. and the condition they are in. Then begin to construct a plan for the restoration work you would like to do. See Illinois Historic Cemetery Preservation Handbook: A Guide to Basic Preservation for more details on constructing a plan.
With a plan in hand, seek permission from the owner to begin work. I think you're better off having a plan when seeking this permission, as opposed to just asking without any discernable idea of what you actually want to do. The IHPA has a Permission to Clean and Preserve a Historic Illinois Cemetery form that gets this agreement in writing and starts the permit-obtaining process (basic work, including cleaning or repairing markers requires a permit in Illinois). Also note "that you are required to demonstrate that you have received proper training in basic cemetery preservation methods before you will be authorized to continue. Work can not begin until you have received a written permit from the IHPA." (IHPA FAQs)
Please also be aware that there are many state and county laws concerning cemeteries. See Stones and Statues: Laws Governing Illinois Cemeteries and the IHPA's "Laws Protecting Illinois Cemeteries" web page for more information. When in doubt--CALL!
The Illinois Historic Cemetery Preservation Handbook: A Guide to Basic Preservation also provides a good deal of information pertaining to preserving marble stones, as well as a visual guide to types of stones and marker styles. It's certainly worth taking a look at for just these resources alone!
The IHPA has an FAQ page that answers questions specific to Illinois cemeteries, but also discusses, in general, why cemeteries become abandoned and why preservation is important. This is also a great read!
This article was written for the May 2009 edition of the Graveyard Rabbits Carnival.
Disclaimer: I am not a lawyer, not am I well-versed in Illinois cemetery laws. What was written above is an interpretation of the various sources presented on the IHPA's website.