This stuff is actually fairly hard, certainly not easy. You have modulation with your signal over it. You need some way to see what is being generated as well as an understanding of the encoding.
It sounds like you don't actually have anything working but occasionally an LED blinks which may mean the code is being decoded right.
Two things that could help are looking at the signal and using a library (like Ken's). These are both challenging and you will learn a great deal. So I am suggesting Ken's library again. You can start straight with the library and do the visualization after.
With Ken's library, guess at the common protocols with your device. Right a sketch to receive. Aim you remote and see if it works. Work through the common protocols until you find one that works. This will also tell you the key mapping, like what key is generated when you press stop. Then you write a sketch using the library to send the signals. (If you done have an IR receiver, you can just try sending signals.)
Ken's site has lots of info on IR and you can look at the protocols.
Another thing you can do is look at the signal from your remote control. There are sketches posted on this site for this: http://arduino.cc/playground/Code/InfraredReceivers
. This will record a bunch of levels that would then have to be plotted. Once plotted, you can figure out the encoding. THis requires reading about the common formats. There are links on Ken's site. This step is fairly hard.
Plotting the IR output of your code would be a good way to debug your code. But it is probably better to start with the library. You will learn a lot by using it which will help you with your own code.