For latitude, 0.001 minutes is equal to about six feet. 0.010 minutes is then about 60 feet and 0.100 minutes is about 600 feet in round numbers.
For longitude, the answer is more complex since it can vary depending on your latitude. At the equator, 0.001 minute of latitude is 6.14+ feet whereas at N 45* (to use your example) the lines of longitude are closer together and 0.001 minute of longitude is about 4.34+ feet.
Hope this helps,
-Buxley
-- Ed Hall (edhall@brillig.com) http://www.brillig.com/ "There's a hell of a universe next door: let's go!" - e. e. cummings