There are a number of web sites that provide free full-text access to theses and dissertations.Howard College Library has a guide with links to free dissertation sites.
Networked Digital Library of Theses and Dissertations is an international organization dedicated to promoting the adoption, creation, use, dissemination and preservation of the electronic theses and dissertations.
Open Thesis - "OpenThesis is a free repository of theses, dissertations, and other academic documents, coupled with powerful search, organization, and collaboration tools."
PQDT Open provides the full text of open access dissertations and theses free of charge. You can quickly and easily locate dissertations and theses relevant to your discipline, and view the complete text in PDF format.