deepsouth provides some great info on how to lobby your legislator. And BTW, when a constituent contacts them, it does make a difference. When many do, it has an impact.
When I served in the Wisconsin legislature I kept track of who was contacting me on what issue. People living in my district would often get a telephone call from me to discuss the issue. Understand something...legislators do not hear from tons of people so when they do, ears perk up.
Whatever you do though, I would caution you about mentioning anything about how you voted for them, or, that you would do so if they supported your issue. Threats never worked for me one way or the other.
Good luck. I know how difficult it is to change the law regarding alcohol. There are so many deep rooted special interest groups out there that want to protect what they have.