Ok well my site got lowered in the search engine rankings a while ago (around august). So most of my pages dont show, even my main page doesnt show in the top 20 pages. I just don't understand why its not coming back to the top especilaly after 4 months. Im starting to wonder whether it will ever come back. What measures can i take to get my site back up the rankings!? (Just to note its never been booted out the rankings)
Can you share your URL? When you say your site doesn't show in the top 20, is that for the domain name as the keyword? You should read through the Google SEO Starter Guide, learn what Google wants, and give it to them. It can be very simple or very difficult, the choice is yours!
As the above said a URL would be a big help , It could be so many things that could "possibly" be the problem . Poor coding , penalisation , Site hacked/manipulated , Reduction of previously held backlinks etc etc etc it really is endless with out seeing what you are facing . Ive known penalisation to be penalised for 12 months , ive also known sites to stay out of the index because of hidden links that a hacker had installed with out the owner knowing, As soon as they were removed the site bounced back . Have you requested a reconsideration request before ? If not check googles webmasters guidelines and make sure your site fits the bill, correct anything that is wrong and then submit a request.
Like Brad says, in order to help, we need a bit more information, what you did (SEO) up until then, what you did arond then, and what have you done since then?
i strongly suggest that you continue to build quality backlinks to your website and update your pages regularly.
Are your still building links for your site? If yes, where you spamming? It maybe sandboxed thats why you can see it on the SERPS. Try doing some link building using high quality sites. Post on authority sites and it might help you get out of sandbox in case you are penalized.