[azmanam]

Not a quantitative list, per se, but the following sites seem to indicate the water solubility trends of primary amines roughly follow alcohols, and tertiary amines roughly follow ethers, with secondary amines somewhere in the middle.  At least two of the sites specifically mentioned that water solubility drops significantly after alkyl chains of 6 carbon atoms or more.

http://en.wikipedia.org/wiki/Amino
http://members.aol.com/logan20/amines.html
http://www.chemguide.co.uk/organicprops/amines/background.html
http://dl.clackamas.cc.or.us/ch106-05/properti.htm
http://www.cem.msu.edu/~reusch/VirtualText/amine1.htm

[minimal]

Great, thanks for the help both of you.

I think the problem was I didn't realize that @ pH of 7, NH4 exists instead of NH3.   The whole problem came about because I read someone elses suggestion of using NaOH and then organic solvent to remove a polyamine.  I assumed that polyamine would have already been NH3 (or equivalent obviously NR3), and that adding NaOH would deprotonate it to NH2-.  But I realize now that that would not exist.
I have a followup question in light of all this...I was always told that a strong acid has a weak conjugate base, and vise versa.  Why is it then that NH4 is a weak acid, but NH3 is also a weak base?  Is it just a very loose rule that a strong acid has a weak conjugate base, and a weak acid has a strong conjugate base?

[Borek]

Is it just a very loose rule that a strong acid has a weak conjugate base, and a weak acid has a strong conjugate base?

This is a very precise rule:

pKa + pKb = 14

Trick is, terms "weak acid" and/or "weak base" are loosely defined.