Hi, Jeff
Zurich has an excellent orchestra, the Tonhallen-Orchester which plays in the Tonhalle. Tickets are between CHF 20 and CHF 150 for normal performances. If you really enjoy classical music, you may consider becoming a member of the Tonhalle-Gesellschaft. Membership costs CHF 850, but you can go to the dress rehearsals before the concerts.
For more info, you should go to
www.tonhalle.ch. The site is also available in English.
For a general overview of what's going on, you should get the magazines Züritipp or the NZZ Ticket, which are sold with the Tagesanzeiger or the NZZ, respectively, on thursdays. You get the NZZ Ticket for free at the Jelmoli ticketcounter and the Züritipp for free at the tourist information in the main station.
Enjoy
Idgie