What is the value of a 1929 US half dollar?

Check the back of the coin near the 8:00 position for the mint mark. There will be a D or S; Philadelphia didn't mint Walking Liberty halves in 1929.

Numismedia lists the following approximate retail values as of 02/2010:

"D" mint mark (Denver):

Very worn condition - $9

Moderately worn - $16

Slightly worn - $30

Almost no wear - $227

Uncirculated - $420 to $5,270 depending on quality

"S" mint mark (San Francisco):

Very worn condition - $8

Moderately worn - $14

Slightly worn - $31

Almost no wear - $253

Uncirculated - $480 to $31,880