On your site. The first and obvious answer is to put them on your site. After all, you have all this knowledge; why not share it with your visitors? You may want to create an Articles page on your site. This will give you a place to put your articles, and any new ones that you write. Make sure to add this new page into your site navigation, and especially to add it to your sitemap page. Add a link to your main articles page on your sitemap, and a link to each new article on your articles page, and you are on your way to having your good content indexed. Make sure your visitors and the search engine robots can find your new pages.
Adding article content not only answers your visitors' questions, it adds to your website. Your visitors will have a richer experience with your site when there is more content. Not only can they buy the widgets you are selling, but they can also learn more about how to select widgets, exciting news from the world of widgets, and so on.
The more pages you add to your website, the better chance the already visiting search engine robots will also pick up your new pages to be indexed. More pages mean more links. Be sure to make an archive of your articles on your website. Always keep your pages in directories close to the root of your site for optimum indexing by the search engine robots.
Submit to the search engines. As always you will want to submit your new pages to the mainstream search engines and directories. In addition, look for specialized, topical directories that deal with your particular subject. There are also many general business directories available.
Submit guest articles. In addition to submitting your articles to the various search engines and directories, think about submitting the articles themselves. Submit your articles to sites that accept guest articles. It may take a little detective work to find some of these locations. You can start small, submitting to lesser-known portals seeking information on your topic. Some sites are focused on one topic; others need articles about all sorts of topics. Get searching and you should be able to come up with a healthy list of sites to submit to. Searching in Google and in categories in Yahoo! and ODP (Open Directory Project/Dmoz) is helpful.
Once you are featured as a guest writer on a website, you will notice that most sites archive these articles. How many articles can you write? How many articles are archived and linked? How many different search engines indexed those pages? You get the idea.
Always include a bio of the author, article re-print instructions, copyright information and a link back to your website. Add an active link in your link text in your submission, or request one for your listing. Be aware of dynamically generated pages - a static URL also increases the chance that the article you have submitted has the optimum chance of indexing by the search engine robots.