Having watching over and over, I found two different viewpoints in backlink building and PR 1. Every backlink is counted and helpful for a site's PR (regardless good or bad backlink) 2. Low quality backlink causes adversed affect to PR of a site Which is correct?
You don't tell us exactly how you checked whether or not you got included. Search for the exact text you submitted, for a better idea of which directories listed you, and whether or not the page is indexed. It can take a month or two for this to show up, because many internal directory pages aren't crawled regularly. If your results are still bad, it could mean at least one of three things: 1. Your directory list is outdated. 2. Your website is unsuitable for most directories. 3. Your submission technique is all wrong. Post an example of your submission text (title, description, url) if you want to know where your problems lie.
I don't think they are worth it. There are better ways of getting backlinks. People seem to think that there are very few ways to get backlinks.
Directories aren't really where its at in terms of traffic or backlinks. They're just extra gravy if you have a few bucks to spare when you see someone advertising submissions for cheap.