Spreadsheets4Engineers

Base shake from a random vibration input defined by a PSD profile.

This online Euler buckling calculator can handle non-uniform sections; various boundary conditions and lateral springs:

http://xl4sim.blogspot.com/2014/02/online-euler-buckling-solver-for.html

A nonlinear buckling version can be found at

http://www.spreadsheets4engineers.com/buckle.html