As directory submission is a vital part, here are some good sites list to help people.
Directory is one of the most important part of Search Engine Optimization. Some good directory sites can give us good back links . If these back links are from good pr sites then it is an advantage for SEO.Here are some examples of good instant link directory.
1. http://isdir.info/
2. http://fastcatalog.info/
3. http://cashdir.info/
4. http://bestcatalog.info/
5. http://www.atdir.info/
6. http://yesdir.info/
7. [...]