I use mecab for morphological analysis. I heard that there are several other types of mecab, but I use mecab because it was recommended by an acquaintance.
The following sites are helpful.
How to install (or rather, the original website)
http://mecab.googlecode.com/svn/trunk/mecab/doc/index.html
Using mecab python
http://d.hatena.ne.jp/yutakikuchi/20130215/1360884220
Part-of-Speech ID Definition
http://mecab.googlecode.com/svn/trunk/mecab/doc/posid.html
Preparation for evaluation of user similarity
From O'Reilly: Set-Valued Programming
http://kiwitobes.com/clusters/blogdata.txt