One thing that is vitally important in your seo project is researching the keywords you are targeting. Get it wrong and even though you may be top of the search engines nobody will visit or care.
If the keywords your looking to rank for are too difficult then go for the longer tail keywords and searches. These are the things that keyword research will find out for you and narrow down your target audience.
Keyword research can be done in a number of ways, both free and paid for.
Here are a couple of good free keyword tools:-
The free google tool is great for finding search volumes for your keywords and also finding related keywords. This tool helps you to find what your customers type into the search engines when trying to find your product. Using the information you can optimize pages of your site for those words.
Keyword eye is a great tool as it shows the results in a tag cloud making it easy to visually see the overall picture. Also lets you export your lists to a text file.
Google insights for search is a great tool because it shows the search volume for your keywords, but also shows if it is a growing or declining trend. If the keywords your optimizing for are dropping in popularity then you may want to target something else.