Auto dealers, still recovering from a late-August sales blitz triggered by the government's Cash for Clunkers trade-in program, have nearly run out of cars.  Faced with nearly-empty sales lots, they're growing desperate for more inventory to sell.

The Detroit News reports, "General Motors Co. dealers want the automaker to ship as many as four times the number of vehicles the company initially planned to build in October."  Citing an "internal report," the News adds, "GM officials were surprised to find dealers wanted far greater numbers than the company had projected. There was higher interest in vehicles such as the Chevrolet Equinox, Buick LaCrosse and GMC Terrain. GM, for example, projected building 8,000 Chevrolet Equinoxes but dealers wanted nearly 30,000."

Automobile Magazine adds, "Not all of the requested vehicles will necessarily be built. The requests do, however, give the automaker a good idea of the current demand."

For car shoppers, the news is mixed.  There is clearly more demand for vehicles like the Equinox and Terrain than GM anticipated - so if you're interested in one of those, you may find it hard to find the vehicle you want.  You may also find it difficult to negotiate the price down, since dealers can be confident that, if they can't reach agreement on a price with you, someone else will be willing to buy the car soon. 

The news also means, however, that dealers aren't closing all of the sales they could this month - they need your business.  If you're interested in a vehicle that is easy to find, September is a great time to buy.  It's even possible to find a close match to a high-demand vehicle.  The Saturn Vue, for instance, is built on the same platform as the Equinox and Terrain, but Saturn dealers appear to have a deeper supply of their compact SUV than GMC or Chevy dealers do.  It may be easy to buy a Vue, and walk away with essentially the same vehicle you would have had if you had bought an Equinox, for a much better price.

It's a situation that won't last forever.  GM is working to meet the demand as fast as possible.  The News notes, "Last month, GM said it was boosting its third- and fourth-quarter production schedules by 60,000 cars and trucks, adding shifts and overtime and reinstating scheduled down weeks at several factories.  Detroit's other carmakers have reported similar increases in demand."

If you're in the market for a new car, check out the U.S. News rankings of this year's best cars as well as this month's best car deals.