For anyone doing internet searches for Mt. Olivet, Mt Elliott, Resurrection, All Saints and Guardian Angel Cemeteries in the Detroit area, you can now search by name at http://mtelliott.com/genealogy
The search will show the cemetery and plot if they are buried at these cemeteries. Beware that some information is in error, some of my family members didn't come up because they were entered wrong, some have the wrong plot. I have visited Mt. Olivet a couple of times (living in Nevada), but I brought my info and stopped in the office, which is a good idea. The cemetery is large and poorly marked. The office help was great, provided marked maps and gave hints on finding the graves. I have not tried the phone number though (except when trying to find a relative while I was there-turns out I was standing on his unmarked grave.) Good Luck on your searches.