First, install the Maven plugin from the Plugin Manager. Then read the Apache Wicket Quick Start. Notice that this is the command line that the Quick Start instructs you to work with:
mvn archetype:create -DarchetypeGroupId=org.apache.wicket
OK, let's go. In the New Project wizard, select the Maven project type...
...then click Add and use the info from the command line to create a new archetype:
...and in the final panel fill in whatever you like...
...finally, click Finish, watch the interesting output in the Output window, and then note that you have an entire new Maven project, populated with the info from the Wicket repository:
At this point, right-click the project, choose Properties, and select a server in the Run panel. Then run the application and you're done. Then take a quick tour of Wicket and use all the other cool resources on the Wicket site!