Serious keyword research.

If you want to get LOTS of traffic from search engines, you need to find out
the exact phrases which people are typing into search engines.
There are free tools available for this, but they're not nearly as useful as the
more comprehensive paid tools.

For example, if you're using the Overture keyword tool for your research, be
warned, its results can't be trusted.
As my Special Projects Manager, Jay Stockwell, likes to point out, the
Overture tool shows you the SAME number of searches for all these
searches:
bikini girls
girls bikini
bikini girl
girl bikini
bikinis girl
girl bikinis
This is obviously nonsense.

The Overture tool is useful to give you a quick rough guide, but NOT for
serious research.
Here's a good tip from "Charlie" on our affiliate forum:
"The harder it is to discover a certain search phrase (getting traffic), the
less competition you will have in the SERPs (for that search phrase). If
a keyword research tool is free and popular, how many competitors will
you have for the phrases you discover there?"

Jay has spent hundreds of hours researching and analyzing keyword
research tools. He's built the best site on the Internet reviewing keyword
research tools - KeywordWorkshop.com.
You need to visit Jay's site whether you're using search engine optimization
(organic SEO) or pay-per-click advertising.