Site Hacked

Sir My three websites have been hacked today. The website were installed at the http://careerblog.in

My websites which have been hacked are

http://careerblog.in/sarkari-naukri

http://careerblog.in/google-trends

http://careerblog.in/india-results

while installing these wordpress blog I had used the email id which of one of my website where all mails are redirected to one ID irrespective of whether that id exist or not.

As I do not remember the email ID which i had used while installing.

So how to resolve this problem.
How to avoid from being hacked in future.

Can you send me new password at the my email ID which I had used while installing these wordpress blog.