Make sure Git is installed on your machine and in your system's PATH. Then simple run in your system's shell:
$ go get github.com/go-sql-driver/mysql
You just need to update your imports. Currently you should have something like this in your code:
import ( _ "code.google.com/p/go-mysql-driver/mysql" )
Replace code.google.com/p/go-mysql-driver/mysql with github.com/go-sql-driver/mysql so that it looks like this:
import ( _ "github.com/go-sql-driver/mysql" )
Contributions are welcome!