The NCAA suggests you are not being RECRUITED until you receive a phone call. The mere presence of a letter therefore does NOT mean you are being recruited. Colleges will send literally thousands of letters w/questionnaires. It simply means you have been identified, which is a good thing.
After the identification phase comes the evaluation phase, when they assess your performance - either by seeing you play in person or on video - relative to others on their potential recruiting list.
Be happy when you get a letter, but don't be satisifed. And do NOT tell people you are being recruited just because you got a letter. The only thing you are doing is setting yourself up for disappointment.