I have found the following documents and tools helpful for various purposes. I make them available here without any warranty, expressed or otherwise, that they will fit your purpose.
If you use them, please let me know if the are helpful.
Uncertainty Calculator 3.2
This is the freeware program developed by Chris Grachanen of Compaq Computer Corporation. It is the best uncertainty calculator available for the money and probably still the least complex to use.
Bear in mind that uncertainty calculator can help you with the calculation of the uncertainty (thus the name), however you still have to develop the narrative explaining where you got the numbers from and what assumptions you made in your uncertainty analysis.
The following links are to the self-extracting EXE file and the explanatory README file, respectively.
Uncertainty Calculator (2 MB)
Uncertainty Calculator Readme (24 KB)
Distributions for Uncertainty Estimation using the ISO Guide to the Expression of Uncertainty in Measurement
This document contains a table with the most common distributions you may encounter, when you estimate uncertainty using GUM. It is also available as a hardcopy. Contact me, if you want one.
