How much do you think a professional logo should go for?
If I had to pick a price, I think a good looking, professional logo should go for around $25-50. It all depends on the designer and how good they are though.
Do you currently have Google Adsense on your site? If so, how much have you made from it?
I have never tried putting Google Adsense on my site, but if I get a few recommendations to I might just try it out.
What do you think is the best thing to blog about?
I would have to say that webmaster is a good niche because if you know what you are doing you can help tons of people out and get good information out there to the public.