Description
^[^,]*\\([^,]*),_([^(]*)_\(([^)]*)\)

This regular expression will do the following:
- separate the string using regex and get Author, Title, and URL
Example
Live Demo
https://regex101.com/r/aB8zQ6/1
Sample text
D:\ebook\comic\Author,_Title_of_Book_(http://google.com).cbz
Sample Matches
MATCH 1
1. [15-21] `Author`
2. [23-36] `Title_of_Book`
3. [38-55] `http://google.com`
Explanation
NODE EXPLANATION
----------------------------------------------------------------------
^ the beginning of a "line"
----------------------------------------------------------------------
[^,]* any character except: ',' (0 or more times
(matching the most amount possible))
----------------------------------------------------------------------
\\ '\'
----------------------------------------------------------------------
( group and capture to \1:
----------------------------------------------------------------------
[^,]* any character except: ',' (0 or more
times (matching the most amount
possible))
----------------------------------------------------------------------
) end of \1
----------------------------------------------------------------------
,_ ',_'
----------------------------------------------------------------------
( group and capture to \2:
----------------------------------------------------------------------
[^(]* any character except: '(' (0 or more
times (matching the most amount
possible))
----------------------------------------------------------------------
) end of \2
----------------------------------------------------------------------
_ '_'
----------------------------------------------------------------------
\( '('
----------------------------------------------------------------------
( group and capture to \3:
----------------------------------------------------------------------
[^)]* any character except: ')' (0 or more
times (matching the most amount
possible))
----------------------------------------------------------------------
) end of \3
----------------------------------------------------------------------
\) ')'
----------------------------------------------------------------------