Last night I installed lxml on my Amazon Linux AMI (ami-31814f58) and it was just as not-straightforward as when my co-worker and I put it on our CentOS server a few weeks ago.
So by referring to the yum log, I think the following covers what I needed to install with yum:
gcc-4.4.5-6.35.amzn1.i686 #for building lxml
libxslt-1.1.26-2.6.amzn1.i686 #this can't be necessary given the line below, right?
… and then I used easy_install (which already was on the system 'far as I know) to install lxml a la:
For whatever reason, the easy_install part took several, several minutes. But I was watching "Season of the Witch" so I didn't mind.--------------