Web of Science:
This will provide you with abstracts only but searches many journals
and provides you with a way of searching forward and backward in the
literature. It is also limited only to abstracts published since
2001.
Google Scholar (http://scholar.google.com/):
This is new so I'm not sure how useful it is. It often gives you
only abstracts or links to sites that require subscriptions or payment.
*To access JSTOR and Web of Science off-campus
you must establish a NetID account(assuming you have not already
done so).