Regarding the Keyword search, there are somany tools available now a days.Some are free and others are paid services. You should do keyword search before constructing a website.
There are three commonly used keyword tools:
• Google Adwords Keyword Tool
Google Adwords Keyword Research Tool
Google is free and gets its information from Google’s own search data and
it is tottally free
WordTracker is an online tools that access a database of search data from smaller search engines and is a paid service
• Keyword Discovery
Keyword Discovery is another online tools that access a database of search data from smaller search engines and is a paid service.
These are all online tools.
There are several tools available for helping determining a page’s competitive strength. Here are a few options:
• LifeTips Page Strength Tool
LifeTips Page Strength Tool is currently free
• SEOmoz’s Page Strength Tool
SEOmoz’s tool is a paid service
There are some professional keyword builders available in net, but most work you can do by yourselves.