RE: simple antenna issue
Nance, the problem is without knowing what electronics are in your plane it is hard to suggest replacment parts, I'm guessing it was a RTF, ready to fly model, most of the time they don't use standard electronics in RTF planes, this means a normal RX won't work as you have to match it to your TX or radio, I would suggest 1 of 2 things, either go back to where you bought it, even if on the net and call them for replacment parts or 2 get someone to repair it, remember your RX and TX have to match channel and frequency
some are AM and some are FM and there are a few different of both freq and channels not to mention neg shift and pos shift
Being new you don't want to get all bogged down with all that just yet
To answer your other question the RX is the easier component to replace as everything just plugs into it. I have one now that a crash yanked the antenna wire out of it that I have to repair