Calling around nets me a better rate, as I can ask all sorts of "what if" type of questions that you can't really get from a basic comparison site.
You'll want to check with your auto insurance too; I get a discount for using the same insurance as my cars, and a multi-car discount, and that definitely helps.
Also consider having as high a deductible as you can reasonably afford. The higher the deductible, the less you're paying, but if something happens, you'll need to be prepared to cover that amount.