Objective C - DiscIdent

I've dabbled a bit in Objective C, but only beginner things that you make from scratch, so this has me a bit stumped. Hopefully it's an easy fix caused only by my ignorance.

I want to utilize the online DiscIdent library (check out DiscIdent for a full description - basically it's an online database that allows you to identify a dvd that is currently in the drive based on its "fingerprint"). They offer a sample code in objective c, which I want to use but am having trouble getting to run. The file that is downloaded is an xcodeproj with most of the dependencies (I had to set up the JSONKit manually). It builds fine within xcode, but since there is no executable designated I cannot "build and run" (it's greyed out). I've tried gcc from terminal to compile into an app, but receive many errors. When I resolve one error, another typically pops up. The difficulty of the whole situation makes me think I'm do something very basic wrong.

So my main question is, how do I run an Objective C code (in xcodeproj form - or maybe I run one of the .m files?) that I did not create myself?

I thought I'd narrow down the problem a bit in hopes of getting a response. There is no main.m file in the files downloaded from github, and encapsulating one of them in a main function doesn't work. Would someone mind taking a quick peek at https://github.com/DiscIdent/objectivec and telling me what exactly I'm supposed to run?