The Search-based Keyword Tool generates keyword and landing page ideas highly relevant and specific to your website. In doing so, the tool helps you identify additional advertising opportunities that aren’t currently being used in your AdWords ad campaigns. The tool goes one step further by tailoring the keywords and other data (such as the amount of competition for the keyword, the suggested bid, and more) based on your language or country/territory settings.
Based on your URLs, the Search-based Keyword Tool displays a list of relevant user queries that have occurred on Google.com (and on other Google search properties, such as google.co.uk) with some frequency over the past year; these suggestions can be found under the Keywords tab, in the New keywords related to (site) section. In the Keywords related to your search section, you can see a broad list of keyword ideas that are also relevant, but aren’t necessarily based on your site.
The keywords are also organized by category. Click any category to expand and view its subcategories. If applicable, you’ll also see the keywords organized by brand names.
The Search-based Keyword Tool compares your website and current AdWords campaigns against actual, past Google search queries to identify additional keywords that might be relevant for your campaigns. The tool compiles a list of search queries relevant to your website that don’t already appear in your AdWords campaigns. By changing your language or country/territory settings, you can view keywords (and corresponding data, such as the amount of competition, suggested bid, etc.) specific to those settings.
With access to the actual terms your potential customers are using when they search Google for your products in your language or region, you may have a better chance of reaching your target audience.
URL for Google Search Based Keyword Tool : http://www.google.com/sktool