Column and Beam Loads

[Russell]

I am doing an addition to my house that will entail adding a beam (supported on both ends with clear span) to support second floor joists and roof above. I am wondering what kind of loads will be on this beam and colums supporting it.

Just for grins I would like to be able to calculate the loads on the beam if it is 18' long supported on both ends with a column and supporting floor joists (for a bedroom) 16.5 feet long with a roof above that. I live in Oklahoma so some snow load can be assumed.

Have already been told that I will need a triple 1 3/4" X 11 7/8" beam to support this. Does this sound right?

I am assuming that this can be supported by 6 X 6's (engineer hasn't called back yet). Does this sound right also?

[Sweep]

Can't tell without the tributary area of the second floor, the old roof and the new roof of the addition. Also need the actual code required loadings for those areas.
Also need the Modulous of Elasticity of the LVL's (should be 2,000,000 psi)