According to the United States Census Bureau, about 3/4 of all U.S. business firms have no payroll. Most are self-employed persons operating unincorporated businesses, and may or may not be the owner's principal source of income.
So small businesses are definitely the backbone of America. About 60% ~ 80% of all new jobs created can be attributed to small businesses.
For folks like me who are interested in starting up a small business and want to participate in discussions for business issues, here is a list of websites that I've found useful.
Small Business Ideas Forum
A friendly place for small business owners to share small business ideas and knowledge, ask questions, find help and encourage others.
These days, you don't have a business if you don't have a website. So being a website owner, this is a forum to pay attention to and social.
Web Design Forums
website design and development discussions.
Web Hosting Talk
Discussions on finding a good web hosting for your website.
Reddit Entrepreneur Subreddit
There are quite a lot of people subscribed to the reddit entrepreneur subreddit, so could be good to look into.
Although not a forum, but the comment section of each blog post serves as a kind of feedback. So commenting is similar to a forum discussion.
I will keep this updated when I find more websites.