I registered a domain name and posted one article on the home page few days before, around 4 days before, it is still not indexed, and the extension is .biz what is the problem?
You just need to add your website on Google webmaster tool. also submit website in to some famous directories,
bookmark your site on a few high PR and high traffic bookmarking site and it will be indexed in no time.
For some reasons I've noticed WP sites indexing faster than others. Even without links. In most cases it will be indexed in less than a week.