Thanks for your suggestions. The LR Baggs I-Beam looks interesting - they make one specifically for a classical guitar.
The problem, though, is that I (attempt) to play flamenco which involves lots of percussive tapping on the guitar top. I talked to the people at the 12th fret in Toronto who specialize in classical guitars (
www.12fret.com). They suggested that the tapping would come through much louder with a contact type pickup than what would be desired. They then said that an under saddle pickup would work but that with flamenco guitars the saddle has to be very low and this undersaddle pickup raises it too high usually. They say that what they generally do for professional flamenco players (they mentioned Jesse Cook so I started listening more attentively) is that they embed a small condenser mic in a column of foam rubber (like from a matress). The column is lightly larger in diameter than the sound hole so that is a good friction fit and the column is slightly longer than the width/thickness of the guitar. They slice the foam and place the mic in the foam aiming towards the waist and slightly towards the treble bout. The foam keeps the mic in place and also helps to resist feedback.
I'm going to try it and I'll let you know how it works.
-Doug