Installation date

C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\Summary.txt:
--------------------------------------------------------------------------
Overall summary
...
    Start time: 2014-11-04 11:58:29     <---
...

Expiration date

The evaluation version expires in 180 days.

Find it with python:

_$: python
>>> import datetime
>>> print datetime.date(2014, 11, 04) + datetime.timedelta(days=180)
2015-05-03

or with SQL Management Studio:

Help -> About

look for the Component name column and see the expiration date (expires in xxx days).