We can give you the code you need to add a signup form to your site. This is the option to go for if you have the room on your home page.
Use a form with a few fields (name and email are mandatory) from your datatabase. You could also ask for questions about preferences. It's a good idea not to ask for too much detail at this stage though. Once you have they email address you can always ask for more details later.
Here is an example of a Form: