The traffic you get from digg and stumble upon can guarantee you some ratings but it wont help you make money .. The real targeted traffic must come from the search engine itself. For that I would suggest a proper SEO and try yahoo answers. Answer a cpl of questions there and sit back and enjoy. I get a lot of traffic from facebook but no clicks. Apart from that articles and classifieds will help you.
with zero budget to generate traffic. First off hit up friends for links on high traffic sites that will do it for free. 2nd submit some articles from your site on digg. 3rd install stumbleupon toolbar and stumble your site. 4th put links in your sig on forums that relate to your topic and make quality posts. 5th link exchanges. 6th get money to advertise site.
Don't be a retard submit with digg for a new site is making digg content and 0 to no help for a new blog because you mirror the title tag ranking diggs pages ******* the only time digg is good is if your a authority site and can rank against them either or your working for nothing again for retards that want you to make them money for nothing.
Get a brain the best way is posting to free groups free press releases and forget the social bookmarking its hype bull**** lies. don't do them any favors.
Alot of the advice already given is great! I would suggest putting most of them to use. Keep trying different strategies out and see what works best for you.