The following list is not a complete list, but based on the site description it may help you narrow down which social sites would be best-suited to your business.

AgentB

AgentB is a place to find and share great deals from across the Internet. Users can discover deals and share them with friends by "buzzing" them up to the homepage. Online Web shops can buzz coupon codes and sales.

Bebo

Bebo is a social networking service where members can stay in touch and connect with friends, share photos, discover new interests and just hang out.

Blogger

Blogger is a free blog publishing tool from Google that lets you quickly and easily share your thoughts with the world.

Daytipper

Daytipper believes that everyone is an expert on something. If you have a tip that is insightful, helpful and original, you can share it on Daytipper. Users can also rate your tips, which can move it up on the homepage.

Digg

Digg is a place for people to discover and share content from anywhere on the Web. As a user, you participate in determining all site content by discovering, selecting, sharing, and discussing the news and videos that appeal to you.

Facebook

Millions of people use Facebook everyday to keep up with friends, upload an unlimited number of photos, share links and videos, and learn more about the people they meet.

Fark

Fark.com, the Web site, is a news aggregator and an edited social networking news site. Users can comment on a daily selection of 50 news articles. "Total Fark" is a subscription service that lets you see and comment on all links submitted by users and not only the ones approved for inclusion on Fark's main page.

Flickr

An online photo management and sharing application that lets people make their content available to the people who matter to them.

Friendster

With more than 95 million members worldwide, Friendster is a leading global online social network. Friendster is focused on helping people stay in touch with friends and discover new people and things that are important to them.

hi5

Hi5 is a social networking Web site where users create an online profile to share pictures, updates and interests with friends.

itaggit

iTaggit is a site that allows you to store and organize information about your items and collectibles. You can interact with other users and read and write blogs.

LinkedIn

LinkedIn is an interconnected network of more than 36 million experienced professionals from around the world. The site can help you make better use of your professional network and help the people you trust in return.

Metafilter

Metafilter is a Weblog that anyone can contribute a link or a comment to. Metafilter breaks down the barriers between people, to extend a Weblog beyond just one person, and to foster discussion among its members.

Mixx

At Mixx, all of the content is user-generated. Mixx makes it easy for people to submit stories, photos, videos — whatever you find interesting, informative, different or fun. You can also see and vote on the stuff that other Mixxers submit.

MySpace

MySpace is an online community that lets you meet your friends' friends. Create a community on MySpace and you can share photos, journals and interests with your growing network of mutual friends.

Netlog

Netlog is an online platform where users can keep in touch with and extend their social network. It is an online social portal, specifically targeted at European youth. On Netlog, you can create your own Web page with a blog, pictures, videos, events and much more to share with your friends.

NewsCloud

NewsCloud is a community of readers who submit, rate and discuss the most important stories from around the world.

Newsvine

At Newsvine, you can read stories from established media organizations as well as individual contributors from all around the world. Placement of stories is determined by a multitude of factors including freshness, popularity and reputation. Contribution is open to all, and editorial judgment is in the hands of the community.

Orkut

Orkut's social network can help you maintain existing relationships with pictures and messages, and establish new ones by reaching out to people you've never met before. Orkut makes it easy to find people who share your hobbies and interests, look for romantic connections or establish new business contacts.

Plime

Plime is a pliable tree of interesting links, cultivated and pruned by everyone. Plime automatically determines which articles are the most popular based on user activity and moves it up the category tree accordingly. In this way, news importance is determined through the interests of the user base (and browsing guests), instead of an editorial staff.

Reddit

Reddit is a source for what's new and popular on the Web — personalized for you. Your votes train a filter, so let Reddit know what you liked and disliked, because you'll begin to see recommended links filtered to your tastes. All of the content on reddit is submitted and voted on by users like you.

Small Business Brief

Small Business Brief provides a daily digest of the best small business articles for our audience. Now the site also allows visitors to participate in the process by submitting and voting on the best stories.

Sphinn

Sphinn is a social site for search and interactive marketers. It's designed to allow you to share and discover news stories, read and take part in discussions, discover events of interest and network with others.

StumbleUpon

StumbleUpon is a free service that helps you discover and share websites with others who have similar interests. The more you use StumbleUpon, the more likely it is that you will "Stumble" across pages you like.

Stylehive

Stylehive.com is an online style club for people who live for fashion, design and shopping. It's where you meet your style muses and follow them as they discover and share their latest finds.

Tagged

Tagged.com is a social-networking destination with over 70 million registered users and over 2.5 billion page-views per month. Tagged helps people keep in touch with their friends and make new ones. The site provides a fun media experience featuring expressive custom profiles, fluid widget embedding, integrated video, chat and more.

Twitter

Twitter is a real-time short messaging service (SMS) that works over multiple networks and devices. In countries all around the world, people follow the sources most relevant to them and access information via Twitter as it happens — from breaking world news to updates from friends.

Webs.com

Webs is a place to inform the world about your business, passions or hobbies and engage others to share their unique ideas, information, photos and videos. With features like blogs, Web stores, member profiles and even group publishing, anyone can bring a site to life on Webs.com.

Windows Live Spaces

Windows Live Spaces is a Microsoft blogging and social networking platform. Users can publish a Weblog via mobile phone, add music lists and manage friends.

Wordpress