Twice now in the past month, my 2001 has not cranked. Dash lights up except for gear. It is at the local dealership now (where it cranked right up - of course)and they find nothing wrong with it after I had it towed in yesterday.Not throwing any codes. Battery is new. Anyone have any ideas?

You turn the key and nothing happens except all the normal start lights light up except for the shift position.
Perhaps the shift position switch is getting intermittent and shifting it around when the problem occurs could determine that.

Next time look at as much as possible on which lights light and any other clues. Perhaps take a day to go and crank it every 15 to 30 minutes and look for more clues.

As you know, it's easier to troubleshoot when it's having the problem.

The battery could be the problem except for not showing the gear.

These buick systems act really strange when a lower voltage is supplied by the battery, either by battery or connection, but if your not getting the dash shift position indicators, battery is less suspect.