For dogs that are scared of loud noises included fireworks, it's a good idea to try and condition them leading up to bonfire night. For example, having the tv on louder than usual, or, like my boyfriend does, playing army games on his computer, with the noise on loud! When I first got my dog, he hated the noise, and would leave the room if he turned the computer on, but now he's used to it, and is a lot better with other loud noises!
You can also get CDs from some Vets that you can leave on during the day whilst you're out. Just warn the neighbours, just in case they think someone's banging round your house! Haha!