Hi Roz ,
I had the same problem , my grandparents on my mothers side were catholic , i searched the cemetary lists online but got nowhere , they lived around what is now Newtown . I went to the Central Library , to the family history section , explained to the guy on the desk what i was looking for , i had their death date , and this very helpful staff member sorted the spool for me to look at , it took a while but i found them , the document told me Handsworth Cemetary .A couple of days later i went to Handsworth cemetary located the office , and had to fill in a short form , a member of staff went and checked ( took about five minutes ) and came back with the location of the grave .They give me a map and i went straight to the grave .( There was a notice saying the charge for a search was £10 , but i was not charged )
The only thing that you might have to be prepared for is no grave , just a location ,my grandparents were buried in 1933 and 1934 , but because the grave was not looked after , all i had to see was a grass plot where the grave had been .
Good Luck
Mog .