Building an online community is lot like a grassroots public relations campaign. Word of mouth carries a lot of weight, and the more recommendations you can get from other people the better your chances of attracting new people are. So once you start your own community site how can build an online community cheaply and effectively? Here are 5 things that you can use to spread the word about your online community without spending a lot of money.

1. Viral marketing – Viral marketing involves using videos, Podcasts, and other new media as a way of reaching people that might be interested in your online community. Sometimes you might have to pay for the opportunity, like if you want to be featured in a Podcast, but videos on sites like YouTube are free. You can make a video cheaply and use that to promote your online community site virally when you use a site like YouTube to spread the video.

2. Blogs – Blogging is very popular and getting features on one or two or ten blogs could be a great way to get people over to your social networking site. In order to get featured on blogs that have a lot of readers you have to do a lot of networking or make sure that your site is really different and unique so that bloggers will want to write about it.

3. Other social networking sites – Creating profiles on sites like MySpace and Facebook for your community site and pointing your friends on those sites back to your own community site can be a reliable way to get new people to join your social networking site.

4. Forums – Using forums can be a good way to get people’s attention but you have to be very careful when you’re advertising your own site on a forum. You don’t want to be accused of “trolling” or using the forum just for promotion. To avoid being a troll you need to be an active participant in discussions on the forum. Don’t just post a link to your website and disappear. Post about useful, relevant things and just include a link to your site as part of your signature.

But remember that people will be deciding whether or not to join your social networking site based on your posts in the forum so always keep your posts on topic and polite. Be professional.

5. Email – Email lists can be powerful tools for getting customers or for getting people to join your new social networking site. Break out your email lists of customers, clients, anyone that you’ve ever worked with and send out a newsletter with the information about the new site.