Welcome to the Q&A Forum

It sounds like you are thinking like this..... "Man, it is really hard to get links from other websites.  I just build a blog and use it to give links to my site." The links from a blog will not pass value unless it gets links from other websites.  Then most of that value will be stuck in the blog and only a tiny amount will pass out through the links that you have to your main site. So, if you really want to support your main site, publish the blog in a folder on the main site and fill with highly linkable content, fantastic content... then every link that hits the blog will count for the link popularity and domain popularity of your main site. With great content the blog can be a fantastic asset on your site.  In addition to attracting links it can be a showcase of your expertise and a reference for your visitors. Now about the .org.... it will have the same weight as a .com.  Google treats all types of domains equally.

Jeremy, The reply I offered is based on the belief you know your competitor's names and want to perform research on specific companies. If you want to perform research on keywords then disregard my suggestion and go with Syed's.

Keyword research is the most important part of any SEO campaign, as it represents your foundation.  All subsequnt work is going to be based on your initial keyword research.  Get it wrong, and you may found yourself spending many wasted hours on keywords which are simply not worth it. If you are new to SEO, my advice would be to get some help with your keyword research, or at least get a second opinion. The Google keyword tool is going to be one of the most important long-term tools you will use, and it will help you to effectively choose and find keywords. However, you must consider how strong the competition is for any keyword to give yourself the best chance. Best of luck.