State of excitement is endless around sales (7)
I believe the answer is:
arousal
'state' is the definition.
(arousal is a kind of state)
'excitement is endless around sales' is the wordplay.
'excitement' becomes 'arouse' (I've seen this before).
'is endless' means to remove the last letter.
'around sales' becomes 'al' (I can't justify this - if you can you should believe this answer much more).
'arouse' with its last letter removed is 'arous'.
'arous'+'al'='AROUSAL'
'of' acts as a link.
Can you help me to learn more?
(Other definitions for arousal that I've seen before include "Awakening; stimulation" , "Sexual excitement" , "Awakening (of emotion, etc)" , "heating?" , "Act of waking (someone)" .)