Follow the Papers
You can look for the newspapers that provided detailed coverage of the deaths of these famous people’s graves. These will have the information when they died and where they were buried. You should be able to find their grave-site with the help of this information.
It is not only a tool for research about various topics but it also has information about personalities that may not be very easily available. You can visit the person whose grave you are looking for and see if the information about it has been given. Most famous people have their own pages and details such as birth and death place and where they are buried have been provided.
You can also visit online forums and meet the people online who are enthusiastic about these personalities. You are most likely going to find the answer right away. If you visit a forum with the given personality’s fans, it is going to be even easier.
Visit a Graveyard
If you are not looking for a specific person’s grave and are just looking to find a grave of anyone famous you can visit a large graveyard in your area. You can check with the administration of the cemetery and ask them if someone famous has been buried in there. You are likely going to find more than one famous person buried in that place and can visit their graves.
Directories for just about anything are available nowadays. You can check these directories and find the grave-site of the famous personality or personalities that you are looking for. This should be able to get you to the destination more often than not.