Wasted in Staines when it's limitless cheap booze (5,4)
I believe the answer is:
table wine
'booze' is the definition.
'wasted in staines when it's limitless cheap' is the wordplay.
'wasted' becomes 'blew' (eg to blow money is to waste it).
'in' means one lot of letters goes inside another.
'staines when' becomes 'tain' (I can't explain this - if you can you should give a lot more credence to this answer).
'it's limitless' says to take the centre.
The centre of 'cheap' is 'e'.
'blew' put within 'tain' is 'tablewin'.
'tablewin'+'e'='TABLE WINE'
Can you help me to learn more?
(Other definitions for table wine that I've seen before include "Plonk" , "Drink with meal" , "Drink with meals" .)