The titles says it all ^^ Any of the student line starters made by Yamaha, Selmer, Conn, King, Yanagisawa would be in the $2000 range and are all fine for learning.
Do you need a high F# key? Tilting Bb spatula? Key adjusters? Then you'd need to jump up to the intermediate, pro or custom level which can cost $5000+.
Buy one online - www.samash.com A good saxaphone will cost you anywhere from 2-5 thousand dollars. You can get them online at most brand name sites. 600-1000 bucks or so, you can shop online at Musiciansfriend.com | 