Haha Its one month,.......................... JOKING efforts and time are inversely proportional. more effort less time but then also you will have to promote your website always. Time cannot be calculated if depends on the right effort and how much effort.
you can try adwords, bidvertiser or adbrite but they all seems to be costlier. better go for some cheaper ppc networks
For me the best way is using twitter. I build my biz reputation at twitter and sent my follower the latest information about my biz.
You can use PPC strategies but it will take som testing to see which keywords convert or you can take the SEO route for organic traffic.
one of the most important things to remember is: never spend more than 10% of your profit to advertise your product (in general; not always I guess).
I suppose it depends on what you mean by "best". If "best" means FAST then PPC might be the best option. If "best" means long term then posting and promoting topics of vital interest to your target audience might be the best option.
adwords is the best way to get traffic to your website fast. when you get traffic to your site fast. you can get results fast so you improve your website conversion which will improve optins and sales. So adwords is the best traffic skill to master but it is also the hardest. it will take alot of work and you will lose money before you see a profit.