One of our dogs was an inveterate shedder — she could shed huge mounds of fur all day long. I could spend a couple of hours every day sweeping up dog fur, and as soon as the dog came back in the house, there were more huge mounds of fur, lying about like snowdrifts. We bought one of the "Furminator" de-shedding brushes, and were amazed at how much fur it removed. The house looked better, and Tango felt better.
In addition to regular exercise and quality dog food, your dog needs additional attention for his health and well-being. His coat should be brushed on a regular basis — long-haired and curly-haired dogs, such as cocker spaniels or poodles, need brushing more often and should have their fur clipped and groomed on a regular basis, while some very short-haired dogs don't need to be brushed at all or clipped at all. All dogs need to be bathed regularly; exactly how often your dogs needs a bath depends on the type of dog, the environment, how much he's outside, and your own standards for canine cleanliness.
Dogs also need regular checkups by a veterinarian. During these checkups, the vet will prescribe heartworm pills and any other medicines the dog should have. Most canine health products, such as flea & tick pills, can be purchased directly from your vet, but often you'll find better deals online. You'll want to be sure you're ordering the brand and dosage recommended by your vet for your specific dog, but as long as the product is a name brand from a reputable company, it doesn't matter where you obtain the product.