Matt:

Cairngorm has a kiltmaker on staff and I can attest that she does quality work. She just adjusted my "best" kilt, which she made for me years ago, and I am delighted by the outcome. They have knowledgeable staff, first rate service and a reasonable turnaround on the order. You could do a lot worse going elsewhere.

John Hart at Keltoi was also mentioned in this thread. He's less than an hour away in Kitchener and he'll do a fine job as well (I'm awaiting delivery on kilt from him in the next week or so).