Keyword Suggestion Tools

Whether you are working on search engine optimisation or a PPC marketing campaign such as Google AdWords, knowing which search engine keywords can bring converting traffic to your site is vital. The ultimate is finding a keyword with high traffic, high conversion and low competition. Below are tools which will provide keyword data, most of them are free:

Google AdWords Keyword Tool
https://adwords.google.com/select/KeywordToolExternal
A version of the Google AdWords keyword tool that can be accessed without having a Google AdWords account.

wordtracker.com
http://www.wordtracker.com/
See also: http://freekeywords.wordtracker.com/
Keyword suggestion services for professional search engine optimisation. Obtain free lists of the top keywords via e-mail.

MSN Commercial Intention of Keywords Tool
Gives you a probability that your chosen keyword has a commercial value to it.

SEOBook Online Keyword Tool
Gives comprehensive keyword data.

The Ten Commandments of Keyword Selection at seochat.com
http://www.seochat.com/c/a/Choosing-Keywords-Help/
The-Ten-Commandments-of-Keyword-Selection/
Article on how to choose the best keywords.

Free Keyword Suggestion Tool from Digital Point Solutions
http://www.digitalpoint.com/tools/suggestion/
Displays Wordtracker and Overture Results. Example search:
http://www.digitalpoint.com/tools/suggestion/?keywords=best&country=uk

Trellian Keyword Discovery
http://www.keyworddiscovery.com/
An advanced keyword research and search term suggestion tool.

SpyFu.com
Lets you see which keywords your competitors are buying and which ones they optimize their site for.

KeywordSpy.com
Tells you what keywords your competitors are using and helps you to find the most profitable keywords.

Keywords list from Voytech
http://www.voytech.com/keywords/keywords_list.htm
List of 10,000 top keywords from Voytech.

The Internet Success Spider
A free tool from Neil Shearing which shows you the major players in your keyword niche.

Keyword Elite
Will do comprehensive keyword research for you.

Brainstorm It! from Site Build It!
A powerful keyword analyzer.

SeoQuake Toolbar
Gives you valuable information about your competitors' sites and tells you how much search engine keyword traffic is worth.