You're probably here because a plugin you downloaded has this listed as a dependency. Simply download the jar and install it as you would any other plugin.
MineSQL is an API for making the integration of MySQL into Bukkit plugins quick and easy. If you find a bug or have an improvement, I'd love to hear.
Server Administrators - Simply download and place in your plugins directory
Developers - See the GitHub repository for further information. There is a readme as well as an example plugin. MineSQLAPI on GitHub MineSQLIntegration on Github