Welcome to the forums.

Is this in the context of web applications? If so, The Web App Hackers Handbook (2nd) covers all of those items extensively: http://www.amazon.com/The-Web-Application-Hackers-Handbook/dp/1118026470/ref=dp_ob_title_bk

www.exploit-db.com hosts a lot of papers, and they likely have some on those topics (the quality here can vary quite a bit). The SANS Reading Room hosts the papers that have been written for their Gold certifications, and they may also have some papers of interest: http://www.sans.org/reading_room/

WAHH2 contains LDAP as well. Even if you have a similar book, I'd encourage you to pick that one up too. It's easily the best book on the subject.

Also, once you understand these types of injection attacks from the perspective of a web application, you should find the same principles are also applicable to other technologies.

If you want to learn more about the nature of these attacks i suggest you look at the very first disclosure of the vulnerabilitiy. A nice example would be smashing the stack for fun and profit regarding to buffer overflows (http://insecure.org/stf/smashstack.html) which gives great information about how the attack actually works. Now there are several sites and papers that outline these attacks for you. Almost all show you the how, but most are missing the why, which i think you are looking for.

after some googling i saw that even wikipedia has a nice writeup explaining SQL-injection. i guess the underground is not the only place any more to find such information.

Oh and remember that OWASP has alot of information also.