The following is a partial list of sites that offer scientific information about human sexuality:

http://www2.hu-berlin.de/sexology/

www.sexualhealth.com

http://www.noah.cuny.edu/sexuality

http://www.shpm.com/topics/sex.html

www.impotence.org

http://www.niddk.nih.gov/impotence/impotence.html

http://www.sojourn.com/~nva/web/

http://www.siecus.org

www.symposion.com/ijt

http://www.pslgroup.com/ERECTILE.HTM

http://www.indiana.edu/~kinsey/ABS/newhome.html

http://www.ncfr.com

www.iashs.edu

http://www.iog.wayne.edu/FR/homepage.html

http://www.aamft.org/

www.ejhs.org

http://www.webkamasutra.com

http://www.webhealthcenter.com/general/sm_index.htm

http://www.healthology.com/focus_index.asp?f=sexual_health

http://www.andrologysociety.com

http://www.psychnet-uk.com

http://www.sivasakti.com (for yoga & tantra)

http://www.oralcaress.com

http://www.sexualpositionsfree.com

http://http://users.forthnet.gr/ath/nektar/kma/main.htm (for animated Kamasutra)