This maybe useful to someone who is ordering using USPS Priority Mail International (6-10 days)
Thursday 20th March - Ordered a bunch of stuff from GGG
Wednesday 26th March - First registered with USPS site
Wednesday 9th April - Found at parcelforce depot!
Total business days from GGG = 14 days
Not sure what US have for Easter, 2 days from above was UK Easter holidays.
I received a USPS tracking number from GGG, go here to track it:
http://www.usps.com/shipping/trackandconfirm.htm?from=global&page=0035trackandconfirmOnce it gets to the UK it then goes to a UK courier, you have to guess which one, in my experience it is one of DHL (sometimes) or Parcelforce (often).
With parcelforce you can track the item using their site:
http://www.parcelforce.com/portal/pw/track?catId=7500082Tick the international delivery option and then the USPS tracking number will work.
Don't be fooled by USPS tracking notes, the UK bit could be wrong, see red below:
USPS:
 Electronic Shipping Info Received, March 26, 2008 
 International Dispatch, March 28, 2008, 10:53 pm, NJI 
 Arrived Abroad, April 03, 2008, 10:31 am, GREAT BRITAIN 
 Into Foreign Customs, April 03, 2008, 10:55 am, GREAT BRITAIN 
 Out of Foreign Customs, April 07, 2008, 10:59 pm, GREAT BRITAIN 
 Attempted Delivery Abroad, April 09, 2008, 6:21 am, GREAT BRITAIN  ParcelForce (what is really happening):
28-03-2008  22:53  CAPE FOREIGN CENTER JERSEY CITY NJ 099 Left origin country
03-04-2008  10:31  International Hub Arrived in destination country 
03-04-2008  10:55  International Hub AWAITING CUSTOMS CHARGES 
03-04-2008  10:55  International Hub AWAITING CUSTOMS CHARGING 
07-04-2008  22:20  International Hub Released for delivery 
07-04-2008  22:22  International Hub RELEASED WITH CHARGES 
07-04-2008  22:59  International Hub En route to delivery depot 
08-04-2008  13:26  National Hub Sorted in hub 
08-04-2008  21:38  Local Depot Arrived at delivery depot 
09-04-2008  06:21  Local Depot Awaiting payment of charges 
So there was no attempted delivery!
Next step, go pick it up, make payment over the counter (17.5% of goods value + £8 admin fee) to help fund government projects, all yours  

Hope this helps someone. Ex