How to import Eagle files
This is not "complete"… sorry… but more than I could easily find on the web at 2/15.
What Eagle files? Why do I care?
If you are just getting started with KiCad, you probably don't need this.
"Eagle" is another PCB-CAD package popular with hobbyists.
There are many files created with Eagle out there on the internet. You might want to use one someday.
"Files" come in many flavors. You might just be talking about a file with the schematic and the PCB for a specific project, using standard components. Or you might be talking about the files for adding components and footprints to your KiCad installation.
I don't even KNOW that you CAN import components and footprints from Eagle files… but I am hopeful.
It does seem that you can import some Eagle board files, and maybe that's a start?
What I know so far….
First catch some Eagle files! There are a lot at Sparkfun.com, in Arduino product descriptions, e.g. that for the Pro Mini
For my expeiments of 02 Feb 2015, I fetched the Arduino Pro Mini files. They were in a zip archive. I created a folder for my experiments, and copied the files I'd found (one .sch file, one .brd) file to it. I didn't have much luck trying to work with the .sch file.
Apparently, (to quote a Nov '14 forum post) you once needed to start pcbnew "separately", "not via the launcher", to access the Eagle Importer under "open file".
Under a standard install of KiCad under Windows 7, this was a bit of an adventure, as direct shortcuts are not provided. (But it can be done, but…)
However, for what I was doing, that didn't appear to be necessary. (I was using Windows 7 and KiCad 2013-07-07 BZR 4022, which appeared to still be the "old stable" version 02 Feb 2015.)
After a couple of false starts, I first checked that the folder I planned to use for the project only had the two Eagle files in it, and then I re-started KiCad. The false starts had included hitting a dead end with the Eagle schematic file, (.sch), so I abandoned that.
I restarted the main KiCad program.
With no project open, I started PcbNew. I said "okay" to the usual message about the fact that no .brd file existed. Then I invoked "File|Open". There was a "board has been modified… discard changes?" dialog, to which I said "yes". ("Yes: I want to discard the blank board, and replace it with one from a file.")
Beware the "Gotch": Even after you get to the right folder, it will look like there are no files available to you. But before you despair, note the little combo box about the "Open Board File" dialogue's "Open" button. Use that to select files of type "Eagle ver.6…" (If you want to import a file from an older version of Eagle, you are, I think, out of luck. Sigh.)
You should see the Eagle .brd file, and it should open.
You can now save that, as a KiCad board, and after that, "go places"… I hope.
I'm sorry this doesn't tell you all you (or I!) want to know… but it may be a start for you…
(Most pages within the KiCadHowTo site are more "finished" than this one is!)