From the ESB conductor page of Talend Administration Center, you can access at any time the Nexus artifact repository containing the two ESB artifact repositories on which all the artifacts to be deployed and started in Talend Runtime are published. To do so, simply click the Open Artifact repository button in the toolbar of the ESB Conductor.
Once connected to your artifact repository, you will be able to access all the available repositories and browse to all the artifacts published in them.
For more information on how to install these artifact repositories, see Installing and configuring Talend Artifact Repository.
The Nexus artifact repository is based on Sonatype Nexus: for more information on how to use it, see Sonatype Nexus's documentation on http://www.sonatype.org/nexus.