I've recently updated the Caching Manager module on the Sitecore Marketplace. The improvements were focused on the UI which I've made to mimic the native design of the content editor. It's a lot more compressed and easy to use. The different cache regions are broken into separate tabs and parts of the form are broken into sections. You can collapse the sections by double clicking on the title bar like you can in the content editor. There's use of Sitecore's icons and the buttons are better defined and the font size is smaller so that more fits on a screen.
This article details how to add fields to the Link Database, how Sitecore uses the FieldTypes.config to add items to the Link Database, issues with the DelimitedField type and how to create your own custom type to use in the FieldTypes.config.