http://www.articlebiz.com/

http://www.articlecity.com/

http://www.easyarticles.com/

http://www.ezinearticles.com/

http://www.goarticles.com/

http://www.excellentguide.com/article/

http://www.anyarticles.com/

http://www.articlealley.com/

http://www.articlemotron.com/

http://www.articlesexpress.com/

http://www.articleson.com/

http://www.bigarticles.com/

http://www.earticlesonline.com/

http://www.ezinefinder.com/

http://www.iarticlebeach.com/

http://www.isnare.com/

http://www.a1articles.com/

http://www.article-mania.com/

http://www.ideamarketers.com/

http://www.aadpro.com/

http://www.activeauthors.com/

http://www.amazines.com/

http://www.answer-site.com/

http://www.articlebeam.com/

http://www.articlebin.com/

http://www.articlebar.com/

http://www.articlecube.com/

http://www.articledepot.co.uk/

http://www.articlefever.com/

http://www.articlefusion.com/

http://www.articlehub.com/

http://www.articleintelligence.com/

http://www.articlekarma.com/

http://www.articlemap.com/

http://www.articlemarketer.com/

http://www.articlerich.com/

http://www.articles4free.com/

http://www.articlesbeyondbetter.com/

http://www.articlesoup.com/

http://www.articlesphere.com/

http://www.articles-submit.com/

http://www.articlewarehouse.com/

http://www.content-articles.com/

http://www.contentdesk.com/

http://www.contentmasterworld.com/

http://www.ezinecrow.com/

http://www.free-articles-zone.com/

http://www.freecontentzone.com/

http://freeinternetarticles.com/

http://www.freewebsitearticles.com/

http://www.freezine-articles.com/

http://www.goarticles.net/

http://www.infonexus.org/

http://www.articlewarehouse.net/

http://www.allaroundsuccess.com/

http://www.articleblotter.com/

http://www.articlecat.com/

http://www.articles4cash.com/

http://www.articlesaz.com/

http://www.articles-online.biz/

http://www.articleteller.com/

http://www.articlewheel.com/

http://www.featured-articles.com/

http://www.freeinternetarticles.com/

http://www.propertymagnate.com/articles/

http://www.articlemaster.com/

http://www.contenttycoon.com/

 

http://www.101articles.com/

http://www.wisearticles.com/

http://www.acearticles.com/

http://www.acmearticles.com/

http://www.addarticle-submitfree.com/

http://www.ababba.com/

http://www.activearticles.com/

http://www.articleaccess.com/

http://www.articleavenue.com/

http://www.article-blogs.info/

http://www.articlebliss.com/

http://www.articleblender.com/

http://www.articleboy.com/

http://www.articlebunch.com/

http://www.articlecapital.com/

http://www.articlecircuit.com/

http://www.articlecrazy.com/

http://www.article-database.com/

http://www.articledestination.com/

http://www.article-domain.com/

http://www.articlefair.com/

http://www.articlefarm.com/

http://www.articlefocus.com/

http://www.articlegarden.com/

http://www.articlegroup.com/

http://www.articlehopper.com/

http://www.articlelookup.com/

http://www.articlemailbox.com/

http://www.articleonlinedirectory.com/

http://www.articlepot.com/

http://www.articlerampage.com/

http://www.articles365.com/

http://www.articles24.com/

http://www.articles4reprint.com/

http://www.articles-4-free.com/

http://www.articlesandauthors.com/

http://www.articlesbase.com

http://www.articleselections.com/

http://www.articles-galore.com/

http://www.articleshelf.com/

http://www.articles-hub.com/

http://www.articles-keyword-rich.com/

http://www.articleskingdom.com/

http://www.articlesmagazine.com/

http://www.articlesnetwork.com/

http://www.articlestack.com/

http://www.articlestash.com/

http://www.bigarticledirectory.com/

http://www.cajun101.com/

http://www.content-corral.com/

http://www.contentfueled.com/

http://www.content-edge.com/

http://www.everydayarticles.com/

http://www.ezinearticles.biz/

http://www.ezine-writer.com.au/

http://www.ezineplug.com/

http://www.findandpostarticles.com/

http://www.free-articles-search.com/

http://www.freebie-articles.com/

http://www.free-content-resource.com/

http://www.freezinesite.com/

http://www.getyourarticles.com/

http://www.geminipublishing.com/

http://www.ireprint.info/

http://www.superarchives.com/

http://www.technoarti.net

http://www.articlewiz.com

http://www.afroarticles.com/

http://www.articlepile.com/

http://www.article-hangout.com/

http://www.articlenews.us/

http://www.articles411.com/

http://www.articlesbase.com/

http://www.articlescorner.com/

http://www.articlesolutions.com/

http://www.articletogo.com

http://www.articletower.com

http://www.articletrader.com

http://www.article-treasure.com

http://www.articletrunk.com

http://www.article-warehouse.com

http://www.articlewise.com/

http://www.findanarticle.co.uk/

http://www.findandpostarticles.com/

http://www.ideamarketers.com/

http://www.jodee.biz/

http://www.miniseo.com/

PR2

http://www.1articleworld.com/

http://www.ablearticles.co.uk/

http://www.allaboutarticles.org/

http://www.articlebag.com/

http://www.articlecorral.com/

http://www.articledaddy.com/

http://www.articlefeeder.com/

http://www.articleforyou.com/

http://www.articleinterchange.com/

http://www.articlejoe.com/

http://www.articlelocker.com/

http://www.articlemax.com/

http://www.articlepeak.com/

http://www.articleportal.com/

http://www.articleprobe.com/

http://www.articlerocket.com/

http://www.articlesearchnet.com/

http://www.articlesindex.com/

http://www.articlesnet.co.uk/

http://www.articlesnatch.com/

http://www.articlesonline.org/

http://www.articlesrightnow.com/

http://www.authorcontent.com/

http://www.bestarticlecity.com/

http://www.goodinfohome.com/

http://www.all-you-need-to-know.com/

http://www.articleaddict.com/

http://www.articlenest.com/

http://www.articles4rss.com/

http://www.articlesrus.net/

http://www.articlewell.com/

http://www.ehealtharticle.com/

http://www.a1-articledirectory.com/

http://www.articlefrenzy.com/

http://www.articlejunction.com/

http://www.article-monster.com/

http://www.articleoptimizer.com/

http://www.articlepipeline.com/

http://www.eclipse-articles.com/

http://www.fetcharticles.com/

http://www.free-article-directory.com/

http://www.articlerealm.com/

http://www.articles4content.com/

http://www.article-search-online.com/

http://www.articlesworld.net/

http://www.directarticles.com/

PR0

http://www.articlesalley.com/

http://www.article-store.com/

http://www.technoarti.net

http://www.finance-business-law.com

http://www.contentarticles.com/

http://www.dezinersplace.com/

http://www.freearticlehq.com/

http://www.hotarticles.net/

http://www.internetmagnet.com/

http://www.ad-matrix.net/

http://www.finance-business-law.com

http://www.articlewiz.com

http://www.articleonramp.com

http://www.articleonramp.com/

http://www.ezinesarticle.com/

http://www.articlemanual.com/

http://www.financemanual.com/

http://www.thehealthmanual.com/

http://ezineprime.hubprime.com/

http://www.articlecritic.com/

http://www.articlecritic.net/

http://www.articlem.com/

http://www.articleobsession.com/

http://www.freearticlehq.com/

And, yes it's effective to submit your articles to these directories. Generally you will get 2-3 links in theme based content. If you have nice article and it's been submitted properly then it can be syndicated to many more article directories.