Chipper, contribute two pounds and nothing more (9)
I believe the answer is:
donatello
'chipper' is the definition.
(I've seen this before)
'contribute two pounds and nothing more' is the wordplay.
'contribute' becomes 'donate' (I've seen this before).
'two' shows that letters should be duplicated.
'pounds' becomes 'l' (L can represent the monetary pound).
'and' says to put letters next to each other.
'nothing more' becomes 'O' (resembles 0).
'l' doubled is 'll'.
'donate'+'ll'+'o'='DONATELLO'
(Other definitions for donatello that I've seen before include "Famous Florentine sculptor" , "Old lean-to (anag) - sculptor" , "Italian sculptor" , "Italian artist" , "C 15 Florentine sculptor" .)