Eu tive problemas para instalar o respeito escasso paralxml mas depois encontrei algumas informações no stackoverflow. Com base nessa informação eu fiz umsudo easy_install lxml com algum erro eu acho que o scrapy tem de instalar:

Razão que cheguei a esse julgamento é que eu repilo eu poderia fazer o seguinte:

Python 2.7.5 (default, Jul 28 2013, 07:27:04) 
[GCC 4.2.1 Compatible Apple LLVM 4.2 (clang-425.0.28)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from scrapy import *
>>> 

Mas quando tento fazer otutorial scrapy Eu recebo seguinte erro:

$ scrapy startproject tutorial
Traceback (most recent call last):
  File "/usr/local/bin/scrapy", line 4, in <module>
    import pkg_resources
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources.py", line 2603, in <module>
    working_set.require(__requires__)
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources.py", line 666, in require
    needed = self.resolve(parse_requirements(requirements))
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/pkg_resources.py", line 565, in resolve
    raise DistributionNotFound(req)  # XXX put more info here
pkg_resources.DistributionNotFound: lxml