January was the worst month for car sales since 1982. So it’s no surprise that rebates are up.

At GM, interest-free financing for 60 months is available on most car models–for people with stellar credit.

Or take the rebate. Especially notable: $2,250 on GM’s recently hot large crossovers, $2,750 on the Chevrolet Malibu sedan (for which owners have been reporting very few repairs on our survey), and $3,000 on the Pontiac G8.

Over at Ford, there’s now a $3,000 rebate on the stylish (to some) but slow-selling Flex. Ford also offers zero-percent loans, but only for a maximum term of 36 months on 2009s. For many models, they’re offering much better deals on leftover 2008s. The 2008 Expedition and Explorer have a choice between a $5,000 rebate and zero-percent for 60 months. You can even get a $4,500 rebate or zero-for-60 on the 2008 Shelby GT500, on which no rebates were previously available.

Chrysler’s doing even worse than other car manufacturers, with sales well under half what they were a year ago. So it’s now having another go at employee pricing–which you’ll find on this site.

As is usually the case, rebates in most cases have been trimmed by $500 to $1,500 compared to levels before this offer, so the end result is that actual transaction prices aren’t much different. There are some exceptions–Chrysler actually increased the rebates on its once-popular minivans. Paradoxically, rebates are larger on those car models for which some demand remains. Chrysler appears to have given up on the others, perhaps realizing that no amount of incentives would make much of a difference.

In the past the SRT high-performance variants were usually excluded from rebates. Not anymore. On the 2008 300C SRT8 (which should still be easy to find) you can choose between $5,500 in rebates or zero-percent for 60 months PLUS a $1,000 rebate, in both cases on top of employee pricing.

What’s the best deal, the financing or the cash? TrueDelta’s pricing tool can help. Price a vehicle against itself, then on the results page specify zero percent financing for one car and the market rate for the other. Hit the button to rerun the comparison and you’ll see payments both ways in a second or two. The zero-percent financing is usually the way to go–if you can get it for 60 months.

Next time: incentives on foreign brands.