Not bad. But on the right sidebar, try to organize the sponsors advertisements with the same sizes. It will look nicer.
I also think that there are to much ads. If there are to many, you don't really see/read them and for this reasons i think less is better.
Looks good. Did you remove the categories widget? Who do you use for adds and have you had some luck with them?
Why just you don't ask them to have the specified and exact size to qualify an advertisement on your site? Anyway, as i've looked you site again, ads are now in same sizes. Good job! Good luck!