Shopping late in the day or on weekends can be a hassle because a lot of people fresh from work may be there doing the same thing. And there are few things less pleasant than sitting in a busy showroom for hours trying to complete a purchase.

Do the wrong thing

"If it weren't for the recent tsunami in Japan, I'd think you'd be able to get a great deal on a Toyota Yaris," Lang says.

According to Ward's Auto, Toyota had enough of its not-so-popular Yaris subcompacts on hand in early March to last for 105 days of sales. In comparison, Toyota had only 32 days' worth of Prius hybrids. That meant getting a great deal on a Yaris would've been much easier than finding a heavily discounted Prius.

But the March 11 earthquake and tsunami in Japan dramatically reduced Toyota's homeland production. So even fewer Prius models are available, and the inventory of Yaris models has been eaten away. It also doesn't hurt that the Yaris gets solid fuel economy at a time when gas is headed up beyond $4 a gallon. The window of opportunity to get a great deal on a Yaris is likely closing.

"The way to get ahead is to do the unpopular thing," Lang says. "Buy the car no one else wants while its inventory is piling up."

So follow the news, adjust your expectations and buy an unpopular car when it's in great supply.

The new and old bargains

Last year, Chevrolet was on the verge of replacing its unloved Cobalt with the new Cruze. In order to keep Cobalt sales moving and the Lordstown, Ohio, plant that built it humming, General Motors put large incentives on it.

"Cobalts were going out the door for $9,995, with $4,000 worth of incentives," Lang recalls.

Older designs facing the end of their production lives are often the most heavily discounted by their manufacturers, so it's good to follow what's coming up. For instance, Honda has announced that a new Civic is coming for the 2012 model year. Right now may be the best chance ever to get one of the current, popular and well-designed 2011 Civics at a discount.

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On occasion, however, a new model may be the best deal. When a carmaker is entering a part of the market it's never been in before, it may discount the new product substantially to gain market share. The most notable example of that was in 1990, when Toyota was determined to establish its then-new Lexus brand and was selling the exquisite LS 400 luxury sedan for about $35,000 -- at least $10,000 less than comparable models from Mercedes or BMW.

More recently, Hyundai kept down the price of its Genesis as it sought to enter the luxury market. And Kia has been aggressive in pushing its redesigned Sorento, a small SUV, as it opened a factory in West Point, Ga., that greatly expanded production capacity.

Market timing

The market for cars is, like the market for every other commodity, one that's driven by information -- imperfect, muddled and contradictory information. So keep abreast of the news, cruise the manufacturers' websites to look for big-money incentives and open yourself up to considering unpopular vehicles that may be great bargains.

The better you know what's going on in the market, the better you'll know when is the best time to strike and make your purchase.