If you search on the internet with "SEO company", "Search Engine Placement", or other similar words, you will find a dozen or even hundreds of companies who claim they can help you get top position on search engines. Of course, not all of them can do so. If yes, why most of them are ranked after the second or latter page?

However, there are definitely over 10 companies that can push your site' ranking. The rule behind is that company who has more reputable ranking charges more money than those that rank lower. Once there is a company who rank No.1 or No.2 in all of Google, Yahoo, and MSN charges over $20K per keyword. That company earned a lot of money and is still live on the internet. However, it was recently penalized by Google. Its pages is still indexed by Google, and PageRank is 7, but can't be found through Google search, even using the company' name. Sites linking to this company seem to be penalized too.

This does not mean that you can't never consider a search engine optimization that ranks very high and already catches the attention of major search engines. But hiring a reputable SEO does not guarantee you will be ranked high. You should not 100% depend on search engine marketing. It is your advantage to keep your site's content attractive. In this way, even without the traffic from search engines, you can still get a significant number of valuable visitors. Doing so requires much input of both time and energy, such as content updating, newsletter subscription, etc.

If you are not sure which SEO to choose, you can just write to each of them and get a detailed learning of each one. Be careful! Some less reputable company may use unethical or even illegal way to achieve top position. For details, you can refer to Google webmaster guide at:
http://www.google.com/webmasters/seo.html

We recommend that you strictly obey search engine's rules. Never break any of them. Otherwise, your sites may be removed altogether.