I downloaded Inkscape 0.47 for snow leopard but none of the extensions work.
I get the error:

Inkscape has received additional data from the script executed.  The script did not return an error, but this may indicate the results will not be as expected.

The fantastic lxml wrapper for libxml2 is required by inkex.py and therefore this extension. Please download and install the latest version from http://cheeseshop.python.org/pypi/lxml/, or install it through your package manager by a command like: sudo apt-get install python-lxml

How do I install this and what am I installing  (I guess from the above it's lxml that needs to be installed)

Having snow leopard inkscape 0.46 will not work so I have to use 0.47 but can't as I need to have pattern along path working (for one)

I have no idea how to install - all I do know is you have to know what you are doing or sudo commands are a bad place to go!!!

Thanks

Gaz