Oh how true that is. Keyword research is important, very important. Finding what people are actually looking for is probably the most important factor.

I even sometimes will beg to differ that being #2 or #3 will drive more traffic than being #1.

A good catch though, so a suggestion to everyone, like Tamar says, choose your keywords carefully which you want to optimize for.

I sometimes use Google Suggest as part of my keyword research, but result counts can be deceiving. The phrase "click here" has 1.98 Billion results, but punch it into any keyword research tool and you'll see just how much traffic that will actually bring you. I think results counts are best used to gauge phrase/language/terminology usage. See what people actually CALL the specific product or service that you're pushing.

How can i do key word research ? Can anyone give me some details about it ?

Lets not forget the use of common sense on the topic. Yes as marketers we can forget what the common schmo may type to find your service or product, but geez, to build an SEO campaign around keywords that no one uses sounds pretty clueless. Do i search for "Sanitary Engineer" or "Janitorial Services". Hmmmmm?

Google suggestion tool and traffic check are good tools to check competition based on ppc but are limited to a sclae of 1-5. I recommend wordtracker. it has a trial you can use for as long as you want...