I just picked up my AWD 2007 IS250 w/ NAV and XM last friday. (12/15/06)
I submitted for bunch of price quotes online and had about 6 dealers call me. I then went to a few sites and found a rough range for the invoice price. You can never find the exact numbers since every dealer, depending on voume pays a slightly different price.
I finally had 2 dealers that were competing for my business and kept lowering each others prices, keep in mind they were both high volume dealers. The smaller guys quoted me a full 2k+ higher and told me they couldn't match. I started it off by calling and saying I got a quote for a IS250 w/ Nav for 34,600. And then it gradually came down. The dealers pay about 34,296 a car and get some rebates if they sell alot.
I told the one dealer i would do it for $34,100 AWD w/ NAV in the black w/ sterling and got XM installed on top of that for an extra 599. They originally quoted me 899 for xm. I told them i would pick up the car tomorrow and got the final price w/ tax before i even got there so I didnt have to deal with their BS.
So when it was all said and done the final price...
$34,100 ( saving of almost $5k, MSRP on the sticker was $39,072, a few hundred UNDER invoice )
plus $599 for XM
Out the door w/ taxes $37,127.
All with a 5.69% loan december to remember promo (average right now is 6.5-7%)
So basically got an IS for around the same as a fully loaded Camry or Accord.
BTW dont EVER pay a destination charge w/ lexus. A good dealer wont even bother to try and slip it in.
If you do some work before you get to the dealer and find one that will give you a definate price over the phone your set. When you submit quote online the dealers KNOW that they have to compete on price for your business. Best thing I ever could have done.