I recently posted "My experience: Refinishing hardwood...." and told about our experience to get a richer stain color. Our contractor suggested a 'water-pop' prior to the stain. The floor is dampened with water and allowed to dry. Then the stain is applied as usual. Wetting the wood causes the grain to raise, or pop, thus the wood accepts more stain resulting in a deeper stain color. Our contractor said there is a bit of technique to doing a water-pop because the person applying the stain cannot step on the water-popped area. Stepping on the area presses the grain back down, so that results in less stain going into the wood. Our contractor did not charge us extra for this step. For him, it was all about our getting exactly the color we wanted.

I realize this is a little late but you might want to try Velvit Oil in ebony. I thought it looked beautiful but it was too labor intensive for me to do 2,000 sq ft. I still have the sample can so I might do my outside office :)
Kimberly

Here is a link that might be useful: Velvit products

Thanks nanj and kinberlyinva for the suggestions! We've actually finally decided on a custom stain mixed by a paint store. We didn't even realize that was an option until a few days ago, so got a sample and think it will definitely be dark enough!

STAIN THE WOOD WITH A BASE APPLICATION OF USING NAPTHA MIXED WITH OIL PAINT ( BLACK ) 30/70.
WHEN DRY REAPPLY - ! GO AS DARK AS YOU PREFER.