After doing "sudo apt-get update", everything is suddenly visible -- including the "kstreamripper" package Brian suggested I search for as an example. Thanks.
I'm wondering, though, if there might still be a bug here -- should I have had to do that "update" manually, or should I have known that this step was needed after I uncommented those lines from my "sources.list" file? -- Can't get aptitude to access universe https://bugs.launchpad.net/bugs/99578 You received this bug notification because you are a member of Ubuntu Bugs, which is the bug contact for Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs