Your visitors will bookmark your web site if it's full of free, original content like articles, e-books, etc.
You could survey your target audience to see which web sites or what type of sites they visit a lot.
Then you could place those links all in one section of your web site.
You could advertise it as a start page.
Use headlines and sub-headlines all over your web site that will grab your visitors' attention.
They will attract them to explore your web site longer.
They could be for your free e-zine, product ads, free content, message board, chat room, etc.
Update the content on your web site regularly.
You'll want to add new content and update the old content.
People want timely information that tells them how to do something 'now', not how it was done 10 years ago.
That's another reason you should constantly be educating yourself.
Provide a free contest or sweepstake at your web site.
It's a fact, people like to win things.
If you can fulfill that need, people will visit.
You can also attract them to revisit by holding one every week or month.
You could also start an opt-in list for people who enter your contest or sweepstake so you can follow-up with them regularly.
Allow people who do not have time to explore your site to download your web site in e-book format.
This will allow them time to view it offline.
Just compile it like you would a normal e-book.
You could also turn it into a viral marketing tool by allowing people to give it away to others for free.
Remind your visitors to promote your web site.
Use phrases like: "Refer Our Web Site To A Friend" or "Link To Our Web Site".
Offer them incentives for referrals.
You could give them free e-books, reports, software and other informational products.
You could also offer them discounts on other products you sell.