There are literally hundreds of web directories on the web however separating the wheat from the chaff has become increasingly difficult for anyone looking to find a good web directory to submit to for some SEO benefit. Many Search Engine Optimisation practitioners will argue that submitting to web directories no longer provides tangible benefit. This argument holds some weight when you consider the flip side that there are hundreds of web directories out there that are not being indexed by Google and are in some cases being discounted by search engines due to practicing illegitimate techniques to entice people to pay for a link in their directory.
The first thing you need to take into consideration when looking for a directory is the discrepancy between purchasing a link and purchasing a review of your website. Purchasing paid links is strictly against Google's webmaster guidelines and should not be encouraged under any circumstances. Purchasing a paid review of your website, however, is not strictly against Google's Webmaster Guidelines and there are many very prominent brands out there offering this service to advertisers e.g. The Yahoo Web Directory is probably the most well-known web directory in the world.
Before submitting to a web directory always check their review policy. This will provide you with the best indication possible on the types of links they are likely to accept in their web directory and will also give you a very strong indication on whether the directory is worth submitting to in the first place. Always apply common sense when submitting to a directory, look at whether or not the directory accepts homepage links or whether it accepts links from blatant spam sites. It's important when practicing an SEO strategy to ensure that you are not obtaining links from bad neighbourhoods as this can impact negatively on how a search engine may view your website.