Go here for a handy conversion utility:
http://www.forumsoftware.com/databank.htm
This is what it said when I put in the numbers:
Live mid-market rates as of 2002.06.08 03:31:24 GMT.
1.00 USD
United States Dollars = 0.685213 GBP
United Kingdom Pounds
1 USD = 0.685213 GBP 1 GBP = 1.45940 USD
So for your 1000 GBP = $1459.40 USD