Ask HN: Looking for pen-testing training material

I am a test automation engineer and am looking to switch branches to penetration testing.

tldr; Anyone have any good realistic pen testing challenges or reading materials which I can use to get a hand on pen testing web apps? I don't need background knowledge as much as I can identify vulnerabilities when I see them, just need something as a guideline where to look/what to use first.

I had a job interview recently and it went well; but the next step is a test where the employer will want to see what I know.

I feel a little queezy as I am great in finding bugs in software but am not always exposed to situations where I have to write exploits (even simple ones like sql injections/cross site scripting vulnerabilities). I have tried some of those challenge sites on the web and can get through a couple before getting to a point where I am actually solving a riddle which is not exactly a practical example. I also have a good programming background so just some sort of practical examples would be nice.

Any help would be appreciated.