Addict tours centrepiece of church, one attracting lots of interest (6)
I believe the answer is:
usurer
'one attracting lots of interest' is the definition.
(a usurer charges lots of interest on loans)
'addict tours centrepiece of church' is the wordplay.
'addict' becomes 'user' (drug user).
'tours' indicates putting letters inside (to tour can mean to go around).
'centrepiece of' says to take the centre (piece from the middle).
The centre of 'church' is 'ur'.
'user' going around 'ur' is 'USURER'.
(Other definitions for usurer that I've seen before include "One lending money at unreasonable rates" , "Person who charges excessive interest on loan" , "Unrestrained money lender" , "Unscrupulous moneylender" , "He takes much interest" .)