Well the Yahoo directory is something I consider a liable source of company's and informational sites, In the UK we have the Yellow Pages book which has all the business on and phone numbers so you can contact everyone.

I find yahoo an online version of that book, and that book has saved my skin many times. You can get listed in of course doing it by hand just keep promoting your site but of course you in competition with a few odd million, It just depends if you are willing to spend that kind of money and make something out of it, do you think you will get that in payback by ad serving programs such as adsense? If so then yes it is worth it.

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