The first place that you should look for sample personal statements is on the website of the school in which you are attempting to get into. If you can find samples of the admission essays of others who have already been accepted into the school then you can really begin to dig deep and find out what will be expected of you. Depending on the school in which you are trying to gain entry to, finding these samples can be easy or darn near impossible. When the latter happens you can always turn to the internet for help. Just as with anything else these days, the internet has an unbelievable amount of websites with samples of various types of admission essays. You can begin by conducting a Google, Yahoo, or Bing search on 'personal statement examples' and then begin to look at the different results that come up.
To help you begin the writing phase, it is advantageous to split the writing task into three parts: the body, the conclusion, and the introduction. You can do so chronologically or follow your own sequence depending on your personal preference and style.