For every business and website there are a few keywords potential customers will type into a search engine in order to find your product or service that will make up the majority of your profit. I call these "grail" keywords. These are the words that you must absolutely show up on the first page of search results for to dominate the marketplace and get a large portion of the available traffic.
You can quickly figure out which keywords are the grail keywords for your industry by signing up for a Google Adwords account and using the keyword suggestion tool. You can enter keywords and phrases you think people may be typing into search engines to find products and services like yours and it will make a list of suggestions. Typically grail keywords are those which have a high number of monthly searches and are also highly relevant to your business. For example_ If you're a plumber you'll find that many people type the keyword "plumber" into Google. Only a few of those people are your potential customers if you're like most plumbers and limit your services to a geographical region. Therefore "plumber", though having the highest number of monthly searches is most likely not your grail keyword.
In another scenario let's assume you're a plumber in Seattle. You may find there is a significant number of searches for the keyword "seattle plumber". In this case it's much more likely "seattle plumber" is a grail keyword because it has a significant number of searches and is highly relevant to your business. Chances are if someone is on the first page of search results for the search term "seattle plumber" and they work as a plumber in the Seattle area there is quite a bit of profit to be made from that keyword. You can find out more about determining the budget for a particular keyword by reading my article entitled "The Keyword Value Formula"
You can make a free website anytime by going to WebStarts.com