You have pages and comments on your site, so make good use of them. Internal links are excellent for link building since you can manipulate everything about them, from the locale on the site to the anchor text.
This is something that a lot of people overlooked, and you should not commit the same mistake. Make sure you steer your content in the path similar to other posts or pages so you can readily link to them.
Also, if you own many sites, interlinking is beneficial unless they are completely inappropriate.