Three main ways in which writers can create synergistic relationships with other writers/sites are by writing guest blogs, having others guest blog on their sites, and getting their customers to write reviews of their products/services.
Guest Blogging
Guest blogging is one of the strongest ways in which you can boost your sites visibility and earn precious backlinks. There are a number of different ways in which you can go about getting guest blogging opportunities. One of the best ways is to regularly read other peoples blogs and leave comments that are interesting, insightful, and add to the conversation. This could also give you a backlink to your site (depending on the commenting system), though it wont necessarily do much for your SEO, it will increase your visibility and may lead a few readers back to your site.
Regular commenting will establish you as a member of the community. Links to your site establish you as an expert and a trusted voice that people can turn to for information and advice. Once these things are known about you, you can approach the blog owner. Send him or her an open, friendly email asking for an opportunity to guest blog. Have the exact blog post you want to write in mind, but also suggest two or three backups, in case the owner doesnt like your first idea.
The standard exchange for a guest blog is one or two backlinks to pages of your choosing, usually embedded in your author bio. Keep the rest of the post relatively free from links back to your own web pages - this is not a free infomercial in written form. You cant pull a fast one here - the site owner is going to check whatever you submit for accuracy, grammar, etc. Attempting to stuff tons of links in the body of your post looks tacky and spammy and defeats the community/relationship-building element of what you are trying to accomplish.
Guests on Your Own Site
Only try to get guest blogging spots on websites that you really respect. Same goes for authors that you bring onto your own site. Using other writers can be a great way to expand the content on your site and take a little of the pressure off of you. If you have a rigorous editorial schedule, an extra blog post written for you by an outside source can give you just a little bit more free time to work on other parts of your site.
Sharing your site with other writers also helps you strengthen your networking and community relationships with other writers. You want to create the kind of relationships that encourage other writers to shout out your website regularly. Keeping traffic active between your site and those in your network is a great way to keep infusing your site with new readers. Many times when someone is doing a guest post on another site, theyll let their readers know via a Tweet, Facebook announcement, or on-site announcement (or all three) that they are doing it. This gives your site added exposure.
Reviews
Getting other people to write for you doesnt always have to be as official as guest blogging. One element of a rich, comprehensive site is products with lots of reviews from past shoppers. Clearly presented calls to action (Click here to review this item!) and reminder emails sent out after you know that the item has shipped and should have arrived (Please review your purchase of [insert item name] on [insert date]!) are two great ways that the industry leaders (Amazon, etc.) get their shoppers to weigh in on past purchases.
Offering an incentive like a discount, store credit, or free shipping can be another way to encourage people to do reviews. If youre not comfortable handing out that much money, consider making it a random drawing: Review this item for a chance at a $25 store credit! Keep in mind, the uncertainty of a benefit for reviewing an item will reduce engagement. Having lots of reviews can pay for itself over time as those reviews help visitors convert into buyers.
Conclusion
We all love writing for our own sites (dont we? Guys? Hello?), but we cant do it all alone - nor do we have to. A vibrant, successful site is one that reaches out and touches not only the lives of its readers, but also other blogs and their readers as well. You can best facilitate this by forming strong bonds with other sites and blogs and getting guest blogging exchanges going with them. Encouraging your customers to write reviews for your site is another great way to beef up the written content on your site and encourage people to buy. Any way you slice it, the more written content you have, the more your readers will know about you and the more opportunities they have to convert.
If you like these guest blogs and want to try out this whole guest blogging thing yourself, check out Zippycart's "Guest Blogger Mondays!" With just a few simple steps, and a bright idea about ecommerce or SEO, you two could enter the guest blogger ranks!