Many places on the Web now offer the free full text for works of literature. These appear in various formats--some in pdf, some in html, some OCR scans, and a few transcribed by hand. The best of these sites are created by universities, scholarly organizations and archival projects. You'll find a selection of these listed below.
Truthfully, the free internet is not a good place to look for literary criticism. You will seldom find serious scholarly works of criticism offered for free on the Web; instead, you will find it in scholarly journals and books of essays which are indexed in library subscription databases and Library catalogues.
However, if you do want to see the free stuff, here are some links that will help you. Be sure to cite properly when you use any of these sources!