Make sure the shifter is bolted up tight to the mount.
Make sure ALL of the tension clips are on the linkages...don't use cotter pins.
Make sure the trans mount is good. If you have a urethane mount, it can contribute to more noise than normal.
Make sure you do not have a driveline, or engine vibration.
If all of the above is in good shape, then you either live with it, or rebuild the shifter.

These are the kind of clips the shift linkages should have on them. We used to call them "Jesus" clips(long story), but some call them "Mickey Mouse" clips. Either way, these hold tension on the linkages, to help keep the rattles down. A regular cotter pin will not work properly.
|UPDATED|10/22/2012 8:17:12 AM (AZT)|/UPDATED|
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Joel Adams
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"