Others
Information retrieval
This is a collection of web sites about Information Retrieval.
Information Retrieval Course
A detailed on-line course of 204 pages about Information Retrieval by C.J. van Rijsbergen, Information Retrieval Group, Glasgow.
http://www.dcs.gla.ac.uk/~iain/keith/
Web IR & IE
Introduction into Information Retrieval (IR) and Information Extraction (IE) on the web with further material, such as links to PhD Thesises and books.
http://www.webir.org/
Information Retrieval & Extraction
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.
http://www.aaai.org/AITopics/html/info.html
Information Retrieval Resources
Assorted links to resources, such as e-books, publishings, lecture material and software.
http://www-csli.stanford.edu/~hinrich/information-retrieval.html
Glossary
A great collection of terms concerning Information Retrieval.
http://people.ischool.berkeley.edu/~hearst/irbook/glossary.html
Snowball
Snowball is a popular processing language, mostly used for Information Retrieval. The website also provides stemming algorithms as libraries for other programming languages.
http://snowball.tartarus.org/
Introduction to Sentiment Detection
This site offers a short article on Sentiment Detection.
http://www.kmworld.com/Articles/ReadArticle.aspx?ArticleID=10270
Sentiment Detection in Political Blogs
The UMBC offers a paper about sentiment detection and opinion extraction in blogs.
http://ebiquity.umbc.edu/resource/html/id/230/BlogVox2-Sentiment-Detection-in-Political-Blogs