I don't know how many of you guy's have seen this site but I use it for work a lot and it would probably help out a lot. http://www.metric-conversions.org/
For simple conversions, like volume, weight, or temperature, I find it much more convenient to just use my Google toolbar. For example, if you want to convert your mash temperature from 66 degrees Celsius, just enter this in the Google toolbar:
66 C in F (don't hit enter)
It will drop down a little tab that reads "150.8 degrees F"