Think outside the box! SEO is just one way to get web traffic.
When you're starting, forum postings are a much better way to build traffic. Just find a forum related to your niche, provide your expert advice, and include a link to your website in the signature of the post.
Other ways to build traffic include:
-selling on ebay (include [email protected]
in the posting)
-online classified ads (like craigslist)
-ebay classified ads (not to be confused with ebay classified - a wannabe craigslist
-answers sites (like yahoo answers)
-write an article for a popular blog
Most of the above are free. I'd pick some of those before throwing money at Adwords. And when you do throw money at Adwords
1. pick a ton of cheap long specific keywords and throw a dollar at them
2. measure the results
3. throw more money at the keywords that result in sales / good traffic
Happy to help,