I've been around this area many times in my life, for errands, courses, anything. It was a high school hangout and I'd like to think that made me very familiar with it. YET, every time I enter the Sheppard Centre, I get lost. EVERY TIME. I know I have a pretty bad sense of direction but I swear this place is a goddamn labyrinth.
And I'm going to have to agree with Lynda that the stores are brutal. Everything is either a cheap luggage store or an out-of-date pharmacy, and the food options are just abysmal. The only things keeping them in business must be the Winners and the fact that there are a lot of office buildings close by, not to mention high schools.
If you're hungry, there are better choices at street level, or take advantage of the subway line and head up to Finch for some great sushi places.