If you have bazaar, you can check it out like so:
bzr branch lp:numpybuildout
To use distribute instead of setuptools use the -d flag of bootstrap.py.
python bootstrap.py -d
>>> import numpy
There you have it, a simple project that can download and build numpy off of the python package index and install it in it's own private directory for use.
update: It was broken for python2.6 and numpy 1.3. However it works again with numpy 1.4