Find five hundred is a hundred too many (8)
I believe the answer is:
discover
'find' is the definition.
(I know that find is a kind of discover)
'five hundred is a hundred too many' is the wordplay.
'five hundred' becomes 'd' (Roman numeral for 500).
'a hundred' becomes 'C' (Roman numerals).
'too many' becomes 'over' (I've seen this in other clues).
'd'+'is'+'c'+'over'='DISCOVER'
(Other definitions for discover that I've seen before include "Find unexpectedly" , "Be the first to have sight or knowledge of" , "Find out about divorces" , "Find through searching" , "Make a new finding" .)