I registered at the Genes Reunited site after it was recommended that I make a visit. This is a UK website, and claims to be the UK's largest family tree and genealogical website.
Prominent on the site's homepage is "Register Free" box, and a "Find a Family Member" search box.
Missing on the homepage is the fact that you can do nothing of substance without paying a fee.
Be sure to read the "Terms and Conditions" (especially the fee schedule) before signing up!