This is a collection of web sites about Information Retrieval.
A detailed on-line course of 204 pages about Information Retrieval by C.J. van Rijsbergen, Information Retrieval Group, Glasgow.
Introduction into Information Retrieval (IR) and Information Extraction (IE) on the web with further material, such as links to PhD Thesises and books.
This site by the Association for the Advancement of Artificial Intelligence (AAAI) gives a great overview about good places to start and further resources of IR.
Assorted links to resources, such as e-books, publishings, lecture material and software.
A great collection of terms concerning Information Retrieval.
Snowball is a popular processing language, mostly used for Information Retrieval. The website also provides stemming algorithms as libraries for other programming languages.
This site offers a short article on Sentiment Detection.
The UMBC offers a paper about sentiment detection and opinion extraction in blogs.