5.5.24 in MLA 7th ed. says-

When a book does not indicate the publisher, the place or date of publication, or pagination, supply as much of the missing information as you can, using square brackets to show that it did not come from the source.  If a publication date can only be approximated, put it after a c., for circa 'around': "[c. 2008].”  If you are uncertain about the accuracy of the information you supply, add a question mark: "[2008?]." 

Use the following abbreviations for information you cannot supply.
n.p. (before colon) = no place of publication given  ex. N.p.: U of Gotham P, 2008.
n.p. (after colon) = no publisher given  ex. New York: n.p., 2008.
n.d. = no date of publication given  ex. New York: U of Gotham P, n.d.
n. pag. = no pagination given  ex. New York: U of Gotham P, 2008. N. pag.

Here are a few full examples-

Print:

Photographic View Album of Cambridge. [Eng.]: n.p., n.d. N. pag. Print.

Michelangelo. The Sistine Chapel. New York: Wings, 1992. N. pag. Print.

Sendak, Maurice. Where the Wild Things Are. New York: Harper, 1963. N. pag. Print.

 Web:

Antin, David. Interview by Charles Bernstein. Dalkey Archive Press. Dalkey Archive P, n.d. Web. 21 Aug. 2007.

Lessig, Lawrence. “Free Databases: More Republicans Call on RNC.” Lessig 2.0. N.p., 4 May 2007. Web. 15 May 2008.

Liu, Aled, ed. Home page. Voice of the Shuttle. Dept. of English, U of California, Santa Barbara, n.d. Web. 15 May 2008.