I grew up in T.O. & lived there till a few years ago. One of my favourite places for a cheap meal was Pho Hung, a Vietnamese place. There's one location on Spadina, which is a great place to be anyway, since that's where one of the Chinatowns is, & also Kensington Market. You can get a great bowl of noodles, bbq pork, & spring roll with all the fixings.
I always found Future Bakery to be a bit sketchy; sometimes food was good, but usually stuff was dry & the waitstaff seemed hassled. But they are open late, especially the one on Bloor near Bathurst. Lots of good Portuguese bakeries on College St. West to choose from, and they're consistently good. Try the custard tarts & corn bread (definitely a different animal from the Southern U.S. version).
Kensington Market has great fresh veggie stores, & cheese stores, & nuts & spices stores and... There are some great empanada places that started out as carts. Just walk around the neighbourhood & you'll find something to nosh.
In the East End, on Gerrard between Greenwood & Coxwell, you'll find Little India. Shan-E-Hind is a great little tandoori place, which will make you faint from gustatory delight, or heat. Oh the naan...
Also, on the Danforth is the Greek area. It's kind of fancied up a bit over the past few years, but there are still some great cheaper taverna type places & the smell of roast lamb will do you good.
Lots of good Sri Lankan, Ethiopian, Polish & Italian food, too. There's a great Italian sandwich shop on Palmerston (or is it Markham?) just south of College where you can get a humongous meatball sandwich. Lots of tomato sauce & cheese. If you want it hot, they just stick hot pickled peppers right in there!
There are lots of really good mid to high high range restaurants there. You can spend a few or plenty bucks. I've never made it to Susur (though I once bussed at Lotus, his previous restaurant), but that's supposed to be quite the experience.
There are a lot of cheaper fast food places too, made by real humans, that are not mega-super-hyper-chains. The Green Mango is a fast cafeteria-style Thai place. Good value for the $$.
I'll write more later if I remember more later!
Anyway, good luck. There are a lot of options for good chow.