This site has a good rundown on Current steel tubesets.
I know there was a site that detailed the diffs between all of
the classic tubesets (i.e. Reynolds 531 & 753, Columbus SL, SLX Aelle etc.)
but I can't seem to find it now, will post link to that one if I find it later.
Here's current info:
http://www.sanobike.com/tubesets.htm