I look forward to finding out more about this opening.
Any good books on the scotch gambit
I will check to see what else there is but off the top of my head--I know Jude Acers did a book on the Italian Gambit which also has very good coverage of the Scotch Gambit. I used this quite a bit thought the lay out is a little strange Most books include it as part of the TWo Knights Defence. Years ago Batsford did a set of books on the Italian Game and Scotch (both by Boterrill) that are excellent. While out of print they are easily available on ABR or other on-line sources. I am not sure how good Pinski's (Everyman) coverage is as I rarely use the book.

Hej Bror,
Years back some pamphlet size books were written on the Scotch by British players. I don't think there is a lot to it, and that is why so many lower ratings want to play it. Scotch, Vienna game, what the hell's the difference? Any good openings encyclopedia or data base would work. Chesskia could probably give you a download (one chess coach to another). I just use King Pawn Openings, by Marovic (Batsford). It is for all those players who don't want to meet the blackside of the Ruy Lopez. I'd rather play the Danish Gambit for White. I have the best information on that. It's Scandinavian too! Too many good black defenses against the King's Gambit. So that's out I suppose. The Scotch is for seekers of the Universal Opening given to Moses on Mount Sinai. "Chess Made Easy" would be an oxymoron. Did Capablanca play the Scotch, or did he just drink it? Three Scotsmen were sitting around drinking when one said, "We need an openin' named efter we Scots, somethin' no too dear." "U'm no sure we should giv' awey a pawn."
The Scotch Gambit would be "the Goring Gambit" (or the Danish Gambit Refused).

There seems to be very little in print on the scotch gambit. What have I missed?
The name. The Goring Gambit. The Scotch Gambit is a misnomer.
Goring - Gambit
Goring - Gambit - German translation 1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. c3?! ...

Lev Alburt and Roman Dzindzichavilli's book Chess Openings for White, Explained is an excellent book which features the Scotch Gambit as the foundation for a White repertoire. The basic idea is to use the Scotch Gambit to reach favorable positions in the Giucco Piano and Two Knights Defense.

The Scotch Gambit owns! It's my opening against 1.. e5.
It is full of landmines for black to step on. You can play it as in the Opening Repertoire for White by Dzindzi and Lev Alburt as a way to reach favorable lines of the Italian game or the Two Knights defense. If black tries to stray away from the main lines in the Scotch gambit he gets smacked.
Or you can play it as a real gambit in the line ala Paul Morphy as in...
1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Bc4 Bc5 5. c3 dxc3 6. Nxc3!?
White has some sick attacking chances and open lines in this position. His e-pawn is really deadly and restricts black's mobility and development. If you get a chance do check out the "Winning with 1.e4" which recommends the Scotch gambit.

Do you play the Scotch? Or do you want to play the Scotch? If so, we welcome you to to join the Scotch Fans Team! We have many forums regarding the Scotch, from how to successfully play this remarkable opening, to how to counter any possible defenses against the Scotch, favourite lines of the Scotch and even how to play as Black should the Scotch be used against us.
Being one of Garry Kasparov's favourite weapons, the Scotch is one of the simplest to learn; yet there are so many possibilities and traps that can arise from the Scotch that it can sometimes catch the opponent off guard. The Scotch immediately gives White an advantage right from the beginning as the center is White's, White has more space, there is more room for development, both central pawns are right in the center of the board and White is still one move ahead.
We are also active in team matches and vote chess games. The time limit varies to suit more people, for example 3 days and 5 days. If you do not know what the Scotch is, check us out!
http://www.chess.com/groups/home/the-scotch-fans-team
Come join our team and show everyone the wonders of the Scotch!
Farbor, In chess Openings for White Explained, by Lev Alburt, it is the line given against 1...e5. I think the authors do a good job showing that unless black goes into a Two Knight Defense, it is very promising for White.
The bad news is that from my perspective if Black does go into a two Knights it can be a tough slog, you're not in any danger of losing per se as white, but I think that Black gets good drawing chances.
Back to good news, if you're below Master strength then this probably doesn't matter.
One more nugget of bad info...no complete games If you're like me, then you really like learning openings this way, so it's kind of bad.
Of course you could read my review over at my blog
http://wangschesshouse.wordpress.com/chess-opening-book-reviews/
(shameless, I know)

Under a rather misleading title, "Danish Dynamite", Karsten Muller and Martin Voigt published a book covering not only the Danish Gambit, but also the Goring, Scotch and Urusov gambits. Two things to note:
a) the diagram will transpose into Two Knights game should black now play 4...Nf6 (there is an error in your diagram - it is black to move in this position), so you need a separate book for that.
b) Muller and Voigt only analyze 4...Bb4 and 4...Bc5

Re Danish Dynamite expensive.
Russell Enterprises - say no more.
Seriously though, it's because the book is out of print and secondhand copies are rare enough to command a premium price in the market.

There seems to be very little in print on the scotch gambit. What have I missed?