Download
Download Drizzle® Server
Drizzle 7.2 (Development)
Latest Development build: Drizzle 7.2
Drizzle 7.1 (Stable)
Latest Stable build: Drizzle 7.1 
Latest Ubuntu packages: Drizzle PPA repository (Install instructions)
Latest Debian packages: Debian Unstable repository
Latest RedHat/Centos packages: Drizzle YUM repository (Install instructions)
Download Libdrizzle
Libdrizzle 5.1 (Stable)
Latest Development build: Libdrizzle 5.1
Drizzle Client Libraries
Drizzle JDBC
Drizzle JDBC is a popular, BSD licensed, JDBC driver for both Drizzle and MySQL.
jar and source files: drizzle-jdbc (README)
PHP
PHP PECL package for libdrizzle client:PECL :: drizzle (Changelog)
libdrizzle C/C++
The C/C++ client is called "libdrizzle" and is developed and distributed together with the Drizzle server. See the above downloads. Using RPM and DEB packages you can choose to install only the client packages and building from source it is possible to build just the client without the server.
Tools
phpMyAdmin
phpMyAdmin now has Drizzle support: Download the phpMyAdmin 3.5.0 series