It's not so much that OTB experience is required for improvement as longer, serious games are usually needed to improve certain skills and focus concentration. One can improve quite a lot playing blitz chess, but building expert calculating, planning, and evaluation skills requires more time than the few seconds one takes between moves in blitz. At least this is the common thinking on the subject.
OTB experience
If that's the case, I'd better start thinking about my summer vacation. Two months, one in New Hampshire, one in Arizona... Know any good chess stuff in those places during June, July, and the beginning of August (specifically near Phoenix in June, and younger-person friendly)?
I play every game against the Computer OTB on a real leather board i got at a garage sale for $1, i move my piece first then wait for the PC to move, then i move that piece. We process things in 2D(On the Computer) different then we do OTB. There is a BIG difference. And i think limiting your game to 2D(Not OTB) could hurt your OTB game. JMHO.
The point is (practice)x(time) = skill and the quality of skill you gain is proportional to the quality of practice. It sounds obvious once you hear it, but due to confusion with the effectiveness of online blitz vs OTB it's worth saying.
So people recommend OTB tournament play because the experience involves both a lot of time and the environment helps push your level of seriousness to a degree that's difficult to reach when studying alone or playing non OTB tournament games. Therefore the opportunity for improvement is much higher in OTB tournament play.
This is the same reason it's often recommended to play higher rated opponents. The harder you're forced to play, and the more mistakes that are punished, the better the opportunity for improvement.
Could you make lots of improvement without any play at all? At the lower levels probably not. After a certain point I think study can replace play but it would take a strong desire to improve and ability to push yourself in your study.
Internet blitz or any games that you don't take seriously give you very very small amounts of improvement. If you play them too often, you'll forget how to play serious chess and it can backfire and hurt your game.
So the upshot for you is OTB tournament play isn't strictly necessary as long as you play fairly long games (let's say at least G/15) and play them seriously. That is, try very hard to find the best moves all the time, and when the game is over, go over it (right then or later) to find your mistakes with the idea of trying to never repeat them again :)
Simple sounding, but hard to follow stuff like always assume your opponent will find the best move, and try to be happy with your move regardless of how your opponent responds to it.
The point is (practice)x(time) = skill and the quality of skill you gain is proportional to the quality of practice. It sounds obvious once you hear it, but due to confusion with the effectiveness of online blitz vs OTB it's worth saying.
So people recommend OTB tournament play because the experience involves both a lot of time and the environment helps push your level of seriousness to a degree that's difficult to reach when studying alone or playing non OTB tournament games. Therefore the opportunity for improvement is much higher in OTB tournament play.
This is the same reason it's often recommended to play higher rated opponents. The harder you're forced to play, and the more mistakes that are punished, the better the opportunity for improvement.
Could you make lots of improvement without any play at all? At the lower levels probably not. After a certain point I think study can replace play but it would take a strong desire to improve and ability to push yourself in your study.
Internet blitz or any games that you don't take seriously give you very very small amounts of improvement. If you play them too often, you'll forget how to play serious chess and it can backfire and hurt your game.
So the upshot for you is OTB tournament play isn't strictly necessary as long as you play fairly long games (let's say at least G/15) and play them seriously. That is, try very hard to find the best moves all the time, and when the game is over, go over it (right then or later) to find your mistakes with the idea of trying to never repeat them again :)
Simple sounding, but hard to follow stuff like always assume your opponent will find the best move, and try to be happy with your move regardless of how your opponent responds to it.
Thanks for the advice Waffles 
Also, I'll check those events out, Estragon, even though I'll get crushed like, well, something that gets crushed easily. :S
I recently read in a thread that if you want to improve, you need to have some OTB experiences (tourneys, clubs, etc.). Is this true, specifically at my skill level (low) and age (early teens)? I want to know because there is not a club or tourney in sight for 100 miles. If it is, then...