Like others suggested, a nearby club will get you started and keeps you interested.
Anytime people just go and buy something, they crash and leave the hobby or simple get bored flying by themselves (there are few exceptions).
You can likely find a used trainer in your club, go to a local rc swap meet or craigslist.

If you get a new plane, $100 buys you a small flimsy toy. You may be able to get a good used trainer for that money. I sold my (like new) 40 size Hobbico Superstar complete with engine and remote for $120 last year. I am sure you can find something like this if you look around.

You just need to decide if you want glow or electric.