http://www.ensmp.fr/~scherer/adminet/constitution.html
La Constitution home page provides an extensive list of links to constitutions and constitutional documents of many countries. Some of the pointers include World Wide Constitutions, the Australian Constitution Act of 1900, the Irish Constitution, the draft of the Romanian Constitution, Constitutional Court of the Republic of Slovenia and more. There are also links to human rights-related sites such as Amnesty International and The Human Rights Web. The contitutional information is available in English. If you read french and are in the mood for literature, there is a link to the ABU (L'association Les Bibliophiles) which has the texts for many classics of french literature