One of my favorite Keyword research tools that I use to find keywords and phrases with is the Google Suggest Tool at Google Labs, as you type in a keyword or keyword phrase it will display keyword additional phrases and the number of search results for the word or phrase.
The Google Suggest Tool is one of my most used keyword research tools, and the best thing about it, is that it is free. I often use it to find niche keywords when I have ideas for new websites. It has many good uses. There are other tools that make keyword research easy, but by far the Google Suggest tool is my favorite of all.
Another great tool that I use frequently for researching keywords and phrase is Wordtracker, although it has a subscription fee to use it is well worth the small amount you must pay to use it. They also offer a free trial that will help you decide if it is a tool you want to use. I recommend it.
Another Google tool is the Google AdWords External Keyword Tool (no AdWords account needed). Not only can you find keywords, you can also sort the results by popularity and even view global search trends (the search volume for the word or phrase). Do you want to see what Google sees in terms on keywords and phrases on your website? Use the “Site-Related Keywords” form on the keyword tool. You can set it to look at one page or the entire site. It is often helpful to see through the eyes of Google when it comes to what words and phrases it sees on your website.
Simple Steps to Check the Keyword Density
Keyword density is always expressed as a percentage of the total word content on a given web page
PPC Keyword Research
Brainstorming keywords that seem relevant to your web site may help to identify keywords
Keyword Research and Strategy
If possible undertake a user analysis to determine the specific keywords searched for in relation to your site.