1. Social Profiles
Sites such as Technorati and Google Profiles are popular in this industry for building profiles and generating free links to your website. On sites such as Technorati, you can input your RSS feed for additional links to your latest posts. Aside from Technorati and Google Profiles, there are several networks out there you can build profiles on, especially in your niche. While you may only build your profile for the link, finding networks in your industry create additional ways of building links through networking.
On the note of networking, asking your friends for links must be one of the quickest, sure-fire link building wins you can get. After all, what is friend for if they can't give you a link? It is not only friends you should ask; they are the quick, easy wins. Don't be shy to ask other people for a link. Whether they are industry-related or other, if you don't ask you don't get. Well, you get what I mean.
A place where people have questioned its value, one thing that should not be denied when building links on forums is the control you have over anchor text. Provided you find a forum where the administrator's are not too strict and they don't nofollow the links, forums are another quick and easy link building win. Plus, they are a place where you can discuss your desired topic with fellow subject lovers. Sounds a bit like a geek fest. Forum signatures are another bonus for link building on forums
4. Internal pages/Blog
If you have your own blog, linking to internal pages within your website will build up your website's link profile, and may even keep your visitors at your website even longer. Over time, your internal pages and blog posts are likely to build their own value (and page rank), so linking from these pages to your website make it even more worthwhile. Other hidden gems on your website with page rank are often the about us and/or contact pages - pages that are one step away from your home page and that are linked to from several the home page and other pages from your website. These can be amongst your strongest sources of link juice - try linking from them to your important pages to build up their value.