Don't bother reading this if you're not ready to do the work.
Amazon has the $400 rebate for purchasing Canon 50D and a Canon Pixma printer.
The problem with Amazon, is their prices fluctuate, so you'll have to get in on this quickly before the prices change up. So far the prices I see today seem to be their lowest prices in a long time.
This is about equivalent to the Canon Summary rebate deal when they were giving away $300, so if you missed it this is your 2nd chance.

The links you'll need to know:
* Canon EOS 50D 15.1MP Digital SLR Camera with EF 28-135mm f/3.5-5.6 IS USM Standard Zoom Lens $1,161.89 http://www.amazon.com/exec/obidos/tg/detail/-/B001EQ4BY0
* Canon Pixma PRO9000MkII Inkjet Photo Printer (3295B002) $446.95 http://www.amazon.com/exec/obidos/tg/detail/-/B001R4BTIA
* Canon EF-S 18-200mm f/3.5-5.6 IS Standard Zoom Lens for Canon DSLR Cameras $591.59 http://www.amazon.com/exec/obidos/tg/detail/-/B001ET6QFY
* $400 Rebate form: http://g-ecx.images-amazon.com/images/G/01/electronics/canon_printers/Canon_ProMKII_Printer_MIR.2009.9.30.pdf

In addition to the $400 rebate, you can sell the Pixma 9000 MK II for $300, and/or the 28-135 kit lens for $300.
Note the Canon 50D w/ 18-200 kit isn't sold by Amazon so it won't qualify for the rebate.

The possibilities are:
Canon 50D body only
Canon EOS 50D w EF 28-135mm $1,161.89
Canon Pixma PRO9000MkII $446.95
Subtotal $1,608.84
Rebate ($400.00)
Sell 18-135 ($300.00)
Sell Pixma ($300.00)
Final total $608.84

Canon 50D w/ 28-135mm
Canon EOS 50D w EF 28-135mm $1,161.89
Canon Pixma PRO9000MkII $446.95
Subtotal $1,608.84
Rebate ($400.00)
Sell Pixma ($300.00)
Final total $908.84

The bottom are just options you can get by adding the 18-200 lens. You can get it elsewhere, but just to give something to compare.
Canon 50D w/ 18-200mm
Canon EOS 50D w EF 28-135mm $1,161.89
Canon Pixma PRO9000MkII $446.95
Canon EF-S 18-200mm f/3.5-5.6 IS $591.59
Subtotal $2,200.43
Rebate ($400.00)
Sell 18-135 ($300.00)
Sell Pixma ($300.00)
Final total $1,200.43

Canon 50D w/ 28-135mm and 18-200mm (2 Lenses!)
Canon EOS 50D w EF 28-135mm $1,161.89
Canon Pixma PRO9000MkII $446.95
Canon EF-S 18-200mm f/3.5-5.6 IS $591.59
Subtotal $2,200.43
Rebate ($400.00)
Sell Pixma ($300.00)
Final total $1,500.43

Let me know what you think.
And please don't go off topic about 7D, new models etc. This is the best deal you can have on 50D right now! Merry Christmas!

There are so many 28-135 IS lenses on the market right now you'll only get 250$, tops. If you get 300 please let me know the sucker you stuck for it.

Your deal doesn't need rebates + Work, it needs rebates + craigs/eBay sales to make the money back.

Sorry for sounding so harsh but these sorts of 'combo' deals have been done with the 40D and many folks got burned on it. It's best just to say you can get the printer for free/sale, etc rather than claiming a 600$ body.

thanks for taking your time. This can be a deal for me (i'm really good at selling stuffs) but probably MOST ppl will pass... it's not that simple