In order to derive more traffic on your website, you should go with off page methods which will help you to derive more traffic on your website 100%.
Social networking (facebook, multiply, myspace, orkut, twitter) and social bookmarking (reddit, delicious, digg, stumbleupon) are good source of traffic.
Post on classified websites like CL or backpage then drive from there. Also post on BitTorrent sites in comments, these get loads of traffic but might be less targeted. Just a few ideas/tips.
IMHO google is still the best... I created a blog with unique content about gentoo and it hits 1000+ unique in 4 month or so with 90% visitor comes from google.
you can get use of social networking sites like twiter, facebook and myspace. Definitely it will help you a lot.
Yahoo Answers , blogging , forum posting etc are some good ways to get traffic without investments. Also now days social media optimization is very much in use to drive traffic , sites like ezdia,facebook,twitter,orkut,etc helps you to get traffic easily, you just have to get patience and first create a good profile on these and grow your network. After that introduce your site to them which will automatically boost your traffic to your site