What are the top sellers on ebay today based on 1) units sold and 2)
dollar volume?

Is this sort of information provided to the public by ebay?  Why or
why not?

I thought this might be an easy one;  if not, please comment and I'll
raise the price.

This earlier answer may be helpful to you:

http://answers.google.com/answers/main?cmd=threadview&id=195060

Great tip!

I tried to answer my own question after looking at the above but I
can't with confidence.

Any experts want to take a crack?

Also, if you can tell me, I am new and see that many questions go
unanswered.  Why is this when google says they have all the expert
researchers they need?

While not exactly addressing your question, you may be interested in
this previous answer:

http://answers.google.com/answers/main?cmd=threadview&id=100413

You also ask why questions go unanswered.  The following pages from
Google Answers describe how questions can be phrased and priced so
that they are more likely to receive answers.  By implication, these
pages suggest why some questions are less likely to receive answers
(low price, convoluted question, etc.).

http://answers.google.com/answers/help.html#howtospecify

http://answers.google.com/answers/pricing.html