Just so everyone's on the same page: US postal rates have gone up across the board last week. Domestic first-class stamps are now 41 cents. And according to the web site www.usps.gov, a postcard or a 1-ounce letter to the UK are both 90 cents. A 2-ounce letter is $1.80 (it's 90 cents per ounce).
Full shipping costs and tables can be found here:
http://pe.usps.gov/text/imm/fh.17.14.htm And by the way, I absolutely hate the USPS web site. It took me 25 minutes to hunt down that link.
::HATRED::