Jack Splat

Reasonable Revenge/Rightful Revenge
Justice Delivered/Delivering Justice
Forged in Fairness
Setting the Record Straight
Jack Delivers/Delivery Jack/Special Delivery Jack

Payback Jack
Going Underground
A Call To Arms
What Goes Around Comes Around
An Eye For An Eye: Jack's In Training
Jack's Reprisals (Do you see what I did there?! )
Jack's Just Deserts (or is that Desserts? I can never remember!)

Jack's Just Deserts (or is that Desserts? I can never remember!)

You always want seconds on dessert.

Don't Mess Around With Jack where we discover he's a huge Jim Croce fan

You always want seconds on dessert.

Brilliant! There's no way I'll forget now. Now, where did I put my second helpings...

Okay, got some more:

Taskmaster/Taskmaster Jack
Stray Dog
Since the Underpass/The Underpass Wake (referencing the tragic accident that took his mother's life)
Solo
Sole Survivor
Life and Times of a Protagonist
Handyman in Training
The Darkening
Stray Cat
The Out Crowd
Outsider

All I can think of for now. :p

Life before Repairs - Before He became Repairman Jack

Early jack was about fairness. No grown man should have to stand in his lawn and cry, the unfairness of it ate at Jack.

Fair Play as a series; and then work Fair into all the titles of the books.

I like where you were going with this! Here are a few more along that line:

In All Fairness

Only Fair

Fair Enough

Don't Mess Around With Jack where we discover he's a huge Jim Croce fan

My brain kept going there too, but I didn't want to say so....

Slipping Into The Cracks
Leading Between The Lines

The Misadventures of Jack
The Best Jobs of Jack
The Joust that Jack Built
Kid Jack's Journeys
Jack's on the Job
Kid Jack
Jack on Track: From Youth to Sleuth

AC