Forum Moderators: open
List in DMOZ.org it's free.
Spend time not money in researching how to get listed into your appropriate categories.
Once listed, go the Yahoo and find the similar category. Almost always Yahoo will list a previously DMOZ editor approved listing.
IMO forget paying for anything else, instead invest time here at the forum to improve your optimization skills.
If time not available - pay someone else the money you would spend at other search engines to learn these skills.
Any listing in DMOZ will propagate the web and to almost every search engine, including Google, MSN, AOL, LookSmart, Teoma, Overture, HotBot, Lycos and AllTheWeb.
Only pay if content is time sensitive.