There are two great deals for US and most EU countries:
1) USA: If you buy the E-M1 you can get a free Olympus FL-300R Compact Flash or Olympus MMF-3 FT to MFT adapter. The PDF form can be found here at Amazon US (Click here)
2) Europe: If you buy the E-M1 within September 30 you will get the HLD battery grip for free. More info at Olympus UK. I know the offer is valid in Spain and Norther European countries too. Not so in Germany and Austria but maybe Olympus will soon add the deal for those countries too.
Preorders in US and Europe (Click on the store name to read price and specs):
Dedicated page at Amazon.
Olympus E-M1 body at Amazon, Adorama and BHphoto, Amazon DE (via DL), WexUK, Topshot Finland, Namencolor Spain, CameraWorldUK.
Olympus M. Zuiko Digital ED 12-40mm f/2.8 PRO Lens at Amazon, Adorama, BHphoto, AmazonDE (viaDL).
Olympus E-M1 with 12-40mm Lens kit at Amazon DE (via DL), WexUK and CameraWorldUK.
Olympus E-M1 with 12-50mm Lens kit at Amazon DE (via DL), WexUK, CameraWorldUK.
Olympus EP-13 Eyecup for E-M1 at Adorama and BHphoto.
Olympus HLD-7 Battery Grip for E-M1 at Amazon, Adorama and BHphoto.
Olympus LC-62D Metal Front Lens Cap for 12-40mm at Adorama and BHphoto.
Olympus LH-66 Lens Hood for 12-40mm at Adorama and BHphoto.