To add the client as a Maven 2 dependency, first you'll need to add the BLC repository to your POM:
<repositories>
...
<repository>
<id>BLC</id>
<name>BLC</name>
<url>http://www.blueleftistconstructor.com/content/repositories/releases</url>
</repository>
...
</repositories>
...and then add the following dependency:
<dependencies>
...
<dependency>
<groupId>com.blueleftistconstructor</groupId>
<artifactId>OAuth</artifactId>
<version>1.1.6.3</version>
</dependency>
...
</dependencies>
You'll need Maven 2.0.8 or greater to build the client. Just run mvn clean package and you're good to go.