Conferences can be an excellent place to market your website to a highly targeted group of people.
However, because of the nature of conferences, being there and communicating your website address is not enough. You will by necessity need to use many of the other marketing ploys to actually get folks to your website.
At a conference people are besieged by information. They will almost never follow with a visit to your website. So you will need to use tricks.
Something which we've tried to moderate success is giving away a special code at the conference which when entered into a form on the website will grant the browser a special surprise. To keep from being abused we took a shipping address at the conference then gave the visitor a speical code related to that address. When the code was entered the gift was sent to the address as entered at the conference. We billed this gimmick as a way to save shipping and other various smoke screens. The bottom line is we wanted them to visit our website when we had a chance to get their attention.
As mentioned this had marginal success. Surely you will think of other fun marketing ploys to use in conjunction with conferences.
Just don't dream they will visit your site because they picked up a flier or business card.