Dixon Home Hardware in Fergus has a good selection of bird feeders and bird seed.

Sharpe’s Farm Supplies in Fergus sells bird feeders, sunflower seeds, and wild bird seeds in bags ranging from 5 kg to 50 pounds.

Gerrie’s Farm Market in Elora sells birdseed (it’s in the back of the store through the door). 

Wild Birds Unlimited in Guelph as all sorts of bird feeders, bird food, and accessories.

Bogles Bird Seed is further afield (on Safari Road just west of Highway 6 near Hamilton) but they are a great source for birdseeds and bird feeders. Of note, they do not use insecticides on their seeds. That’s a tweet worth posting.