I don't play trombone. I acquired a vintage Elkhart by Buescher trombone. The serial no. is 59xxx. How old do you think it is, and how much do you think I can sell it for? It's in fair shape, and a novice like myself can get notes coming out.

Any model number? Is there an F rotor? It's really hard to answer your question without more information. What makes you say it's a "vintage" horn other than the fact that it's old?
Being able to get a sound out of it really isn't a good determining factor. I can get a sound out of a paper towel roll tube. Doesn't mean much. What's the condition of the slide? Is there any wear on the chrome inner slide plating?
How far do you have to tilt the slide before it drops?
How much of the laquer is intact?
What is the diameter of the bell?
Without this information, I'd have to stay on the safe side, assume you got a old student trombone that most likely needs a chemical cleaning and a slide job, and say you could get about a hundred bucks for it. But your answers to the questions could change that significantly.

thanks. No model no., unless "97" is a model. No F rotor. I'm sure it's more student than vintage, but there is some etching on it, the Elkart Logo, and knowing vintage saxes, etching always means something. The inner slide plating appears in good shape. The original lacquer covers about 75% of it. The dia. of the bell is 7". As for sound, I meant as a novice, even I can play a scale somewhat in tune. I don't mind selling it for $100 or so, but if it were worth a whole lot more, I'd rather it go to someone who knows trombones.

Sorry to say, it doesn't sound like you have any real treasure there, but if it's a playable horn, you could get the hundred bucks for it. considerably more if the slide is good. get a trombone player to test it out for you.