Thousands of Old Blogger URL's still showing up

Hi,
It’s been 8 months now and I think my SEO is getting affected. Every day there are lots of weird URl’s that comes up in my webmaster tools as 404 errors. I check my redirection logs of 404 and there is currently 40k+. I don’t know what’s wrong here. Can someone help. I did some manual 301 permanent redirect especially for mysite/xx to mysite/category/xx.

Please someone help there are so many URL’s that I don’t even know what they exactly are.

My site: http://www.thenewipadblog(dot)net

Please help,
Rahul

http://wordpress.org/extend/plugins/redirection/