Evidence of poor penmanship: I especially note a good deal around end of book (7)
I believe the answer is:
inkblot
'evidence of poor penmanship' is the definition.
The definition suggests a singular noun which matches the answer.
'i especially note a good deal around end of book' is the wordplay.
I cannot quite see how this works, but
'i' is found in the answer.
'note' could be 'n' (abbreviation) and 'n' is found in the answer.
'deal' could be 'lot' (synonyms) and 'lot' is found within the answer.
'book' could be 'b' (abbreviation for book) and 'b' is found in the answer.
A single letter 'k' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for inkblot that I've seen before include "Result of pen leak" , "meaningful stain?" , "Stain of various shapes and colours used in the Rorschach test" , "Something used in Rorschach test" , "Mess made with a pen" .)