When my website was first picked up by Google, we ranked highly for a number of our most important search terms. Since then, our rank has gone down. Do I need to resubmit my website in order to get the better search engine results again?
It's not uncommon for new websites to achieve top results when they are first indexed by Yahoo and Google, but for the results to gradually drop off over the next few weeks. We know that the search engines favour new / fresh content, but it's unusual for any new website to consistently do well from first launch. It takes time for a site to establish or attract inbound links, traffic, and indeed trust. With Google, the period of time from first indexing a site until it starts to do well in search results is often referred to as "the sandbox" effect.
Google have claimed there is no such thing within their algorithm, but have also said that it's entirely understandable why so many people believe there is such a sandbox. However, it's just the standard algorithm at work. A new site has little or no quality inbound links, probably little traffic, and no trust rating - such as from site longevity.
Therefore, resubmitting your site to the search engines is not going to make any difference. What you need to do is work on your content to improve it, and build on it. Offer as much new and genuinely interesting content as you can in the hope of attracting those all important inbound links, naturally. If you can, offer something unique on your website that sets it apart from your competitor sites.
A famous man, Earl Nightingale, said in his famous book "The Strangest Secret" that, "...to increase ones sales, one merely has to increase ones service". Similarly, if you want to sell less, just reduce your service. The same thing applies to your website as regards the content. If you want it to do well on the search engines, including the all important Google, you must increase your offering - it must stand out from the rest.
Take every opportunity to add and improve your content.