The Freedom From Religion Foundation, based in Madison, Wis., is a national association of freethinkers (atheists, agnostics) that has been working since 1978 to keep church and state separate.See More
"Hello Loqman Bouroh
Welcome to this internet world of rationality and peace, of common sense and freethinking wisdom. You will find many like-minded people here.
You are invited to join the friendly busy group…"
Groups have their own forums with various levels of activity. I suggest checking to see when the most recent activity was before joining a group. You can find group here: http://www.atheistnexus.org/groups
Blogs are another way of starting conversations, though, because it's a blog, they tend to be more one sided. Still, you'll get feedback, which may be what you're looking for sometimes. Blog stuff is at http://www.atheistnexus.org/profiles/blog/list .