Thanks to both of you. How long should I wait to see if the problem
goes away? It's still there after 2,000 miles. I did not mention that
the car had over 500 miles on it when I purchased it; is this normal,
and is it possible someone could have damaged the engine during this
time period?

It's really starting to bother me, because I recently drove 2 other
honda accords (2004 and 2003) because they belonged to my relatives.
They had 10,000 and 43,000 miles respectively, and those cars felt
great (little or no engine flutter).