Prerequisites: Debian 4.0 Etch (or higher), installed PostgreSQL 8.3, existing database in postgres
1. Install the postgresql-contrib package via apt
apt-get install postgresql-contrib
2. Switch to your postgres user
su - postgres
3. Open the psql interactive terminal with the following options database, user, password and the installation file for the fuzzy string functions
psql -d myDatabase -U myUser --password myPassword -h localhost -f /usr/share/postgresql/8.3/contrib/fuzzystrmatch.sql
Afterwards you can use the soundex, levenshtein, metaphone and double metaphone functions in your sql statements.
Offical documentation about the fuzzy string match functions: http://www.postgresql.org/docs/8.3/static/fuzzystrmatch.html
