The Rogue Agent: The Accidental Sorcerer, Witches Incorporated, Wizard Squared

BOOK 1: THE ACCIDENTAL SORCERER
Gerald Dunwoody is a wizard. Just not a particularly good one. He's blown up a factory, lost his job, and there's a chance that he's not really a Third Grade wizard after all. So it's off to New Ottosland to be the new Court Wizard for King Lional.
It's a shame that King Lional isn't the vain, self-centered young man he appeared to be. With a Princess in danger, a talking bird who can't stay out of trouble, and a kingdom to save, Gerald soon suspects that he might be out of his depth. And if he can't keep this job, how will he ever become the wizard he was destined to be...

BOOK 2: WITCHES INCORPORATED
It's a case of espionage, skullduggery and serious unpleasantness

And it's also Gerald's first official government assignment. He's hunting down a deadly saboteur, and time is quickly running out. Old enemies and new combine forces to thwart him. Once again, innocent lives are on the line. He needs his friends. He can't do this alone.
But Princess Melissande and Reg have troubles of their own. With the help of Monk Markham's brilliant, beautiful sister, they've opened a one-stop-shop witching locum agency, where magical problems are solved for a price. Problem is, the girls are struggling to keep the business afloat. Things are looking grim for Witches Incorporated - and that's before they accidentally cross paths with Gerald's saboteur.
Suddenly everybody's lives are on the line and Gerald realizes, too late, that there's a reason government agents aren't supposed to have friends...

BOOK 3: Wizard Squared
When the staff of Witches Incorporated receive a visitor from an alternate reality, they are shocked to learn that life in the parallel world next door is anything but a bed of roses... and it's all because of Gerald Dunwoody.
At a crucial moment in time, their Gerald turned left... but the alternate reality Gerald turned right. Now the parallel world next door is in the grip of terror, staring down the barrel of a thaumaturgical war -- a war that threatens to spill across the dimensions and plunge every reality into a nightmare.
The only person who can stop a rogue wizard gone mad is another rogue wizard. But what do you do when another rogue wizard can't be found?