I like Frontline Plus the best. You will find ticks on the dog even if you use one of the topical products. They do not repel ticks, they only kill them after they become attached. My experience has been that the dead ticks fall off 4-16 hours after they become attached. The ticks around us have been really bad too. I have found lots of them on the dogs, and I had one on my head after a trip to the dog park (yuck!). Thank goodness they have all only been American dog ticks and not deer ticks. There are also some natural flea and tick repellent ideas- like garlic, and I have read about putting a few drops of certain essential oils (rose geranium oil is one of them, I think) on the dogs collar to repel ticks. I haven't tried it yet, though.
Bridget, Summer, and Duke