Just to amplify what Peter said about the Adobe Photography Plan, Bridge also comes with the plan so if you don't like Lightroom's cataloging system for one reason or another you can substitute it with Bridge.That said, I've always found Bridge to be a bit clunky although it's gotten considerably better lately. And, as Peter said, it's fully integrated with Photoshop which can be a big help. Lastly, it also supports Adobe Camera RAW so you can do much of the same editing in Bridge that you would do in Lightroom. I admit, however, that I've never used ACR in Bridge.
Many Pros prefer an application called Photo Mechanic to handle their cataloging. I once used a very, very early version of this program and wasn't particularly impressed. Lately, I've become reacquainted with it and may actually give it another try. Alas,it's also a paid application.
--Ron