There's no end of cats here (4,2,3)
I believe the answer is:
isle of man
'cats here' is the definition.
The answer is a location as well as being a singular noun. This is suggested by the definition.
'there's no end' is the wordplay.
I cannot really understand how this works, but
'there's' could be 'n' (I've seen this in other clues) and 'n' is present in the answer.
'no' could be 'o' (O resembles 0) and 'o' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
'of' is the link.
Can you help me to learn more?
(Other definitions for isle of man that I've seen before include "TT venue" , "directed by Douglas" , "Here are Peel, Douglas" , "British Crown possession" , "British outpost of the Gaels" .)