I used edmunds.com to send email to dealers.

I bought SL with premium and leather package around new year. It was 5000 under MSRP. For LE, I think there is more room to negotiate. Dealer said there is 600 worth upgrade included for free. I think the upgrade worth at least 100.
You can check edmunds.com for how much others paid. You can also contact dealers a little far away.
I bought it in Houston.
Also the 2010 is out soon. The price should be better at this time.