Till last week, my blog used to come up at second place in google search result for the term 'free logos download'. But now it is nowhere to be found in the results. I made the mistake of changing the permalink structure of my blog, so visitors were getting 404 errors as I did not use any permanent redirection method. Now I have reverted to the same old permalink structure considering it has been only a week, so will my site rank up? I did not make any major change to my homepage's except for some html coding to improve the appearance. But the content is same as it was before. Thanks.
See you don't have content and relevancy of Free logos download in your page. You need to add the content in your site that should be keyword stuffed. get backlinks from good pr sites you will get your position again.
Some time by spamming we can send that website at top but after some time it will go down, because we have not strong links and not in proper way. At filtration time Google will find out this spamming.
Wow I don't see you in page 1 , 2 or 3 , did you have some malware or something? That sucks, I hope they reindex you back at the top. Did you switch servers or something?
The best thing you can do is to create an account in Google Webmaster Tools (if you do not have) and resubmit your feed to Google.
Sometimes google dances around your site. Your likely to come out even higher then you were in a few days.