Dragonborn Books

My son loves Dragonborn.  He plays Skyrim because there is a "dragonborn" in that.  He wanted to get all the Doctor Who episodes on DVD that feature the Draconians, and in every game we play that is the character race he wants.

Well...not every game has them.  But there are a lot of great third-party publishers that feel the same way.

Good thing for me I know about Goodman Games.
They have two products out, The Complete Guide to Dragonkin (for 3rd ed) and Hero's Hanbook Dragonborn (for 4th ed).

The Complete Guide to Dragonkin
This book is the older of the two, so let's do it first.
76 pages, covers, OGL.  Pretty packed really.  A brief intro and some background on dragon-kin and how they are all connected to each other (an interesting touch).  This assumes that a lot of different races inter-bred with dragons like humans, orcs, goblins and of course kobolds. So we have a variety of bloodlines; half-dragons, dragon-touched and "wyrm-bred".
The Half-Dragon Racial Template is presented and the associated powers.  If you are playing 3.x/Pathfinder and want to play a "Dragonborn" character then this is a great book.  It predates the Dragonborn in 4e and the Dragon bloodline sorcerer in Pathfinder, so a Pathfinder update would be nice to have, but still this is a solid book.
There is a lot in this book. It even covers how these races view, and sometimes worship, the dragons they are related to.  There is a chapter on Dragon magic which includes new spells and "dragon egg sculpting".
There is not much in the way of news monsters, but I think that is fine.  There is a Dragon/Kobold crossbreed that works well as an antagonist. Especially if your players tend to laugh when you throw kobolds after them.
I compare this book rather favorably to their Complete Guide to Fey.  It was because I owned that book that I felt comfortable picking up this one.  I was not disappointed.

Hero's Hanbook Dragonborn 
99 pages, GSL, covers. There is a quite a lot in this book.  While Goodman Games could have used a lot from their previous book (The Complete Guide to Dragonkin) this one has a completely different approach.  Dragonborn are well established in D&D4, so none of that material is repeated here. Instead the book covers different clans and variations of Dragonborn.  There is also a lot of crunch to go with the fluff.  Frankly Dragonborn need a lot more "fluff". Unlike all the other fantasy races, Dragonborn/Dragonkin are really a creation of D&D.  Sure there have been other types in the past, but even in the early days of the game their origin is purely a D&D one. That gives this book a lot of room to run.
There is also a nice collection of items to help give this race a sense of history. Plenty of powers for Dragonborn characters, options and magic items.  If you are like my son and love to play Dragonborn in 4e then this is a great book to have.

This book though suffers from the fate all 3rd party GSL books suffer and that is the material is not in the character builder.

In the process of reading these books I became aware of other ones, not by Goodman Games though.

One of the first is from Barrel Rider Games, The Dragon and it is only a dollar.
Again, I don't expect a lot for a buck.  Barrel Rider Games though gives you a whole class for a buck.

This one is a bout Dragons as a class/race.  Not Dragonborn or Dragonfolk, but full blown dragons.
Now my first thought is these characters could be unwieldy in a group of adventurers or even overpowered.  That is best left to the Labyrinth Lord to decide really.
The book is five pages: Cover, 2 pages for the class, and 2 pages for the OGL and the Labyrinth Lord compatibility notice.
There seems to be a bit missing though. I would have liked have seen a little on how to play this character class and what motivates them to adventure.

Fehr's Ethnology: Dragonblood is another one for Pathfinder by Purple Duck Games, a name I have grown to like.
This one is pretty good really. Nice art, clear easy to read text and 7 pages of content (1 full page art, 1.5 of OGL and ads for 10 total pages).  Simple race rules with not a lot of fluff, but a lot of crunch. There are some alternate racial characteristics and some feats.  There are class suggestions and suggestions on play.  For 10 pages it is really packed full. My son has been using this in our 3.x game now for a bit and we like it the most out of the many free options we have also found.  At $1.25 it is an absolute steal.