Need help: Train from Munich to Zurich??

"All sites I've checked say "compulsory reservation" required and that I cannot book this ticket online."

I have to wonder what sites you've checked. Nowhere on the German Rail website do I see anything about "compulsory reservation" required, and I see plenty of connections bookable online, some of them with fares as low as €39 for non-refundable, train specific, advance purchase tickets. For full fare tickets, I see fares as low as €66,60 for a EuroCity (EC) train.

Oh my goodness, I'm so sorry, I wrote the wrong leg of my trip in my email. I meant to say: Zurich to Venice. Thank you for your response as it "woke me up" to the fact I incorrectly stated which leg I was asking about! BTW, I have used raileurope, europerailways, and bahn.de to check on the Zurich to Venice leg - but perhaps I am missing something (like I said, it's only my 2nd trip to Europe!) Thank you very much.

The Bahn has absolutely the best schedule information on the net, but they don't show prices for routes for which they don't sell tickets online, that are completely outside Germany. So, unless you want to ticket Zürich to Munich and then Munich to Venice (the long way around), you wouldn't find bookable routes on the Bahn. And you can't book anything online from Italian Rail. You might be able to book Zürich to Venice through Swiss Rail (www.sbb.ch). Even if they don't show it for online purchase, they might be able to email you with an offer.

Yes, that looks like the way I'll have to do it - through sbb! Thank you so much Lee, I really appreciate it! It's fun learning too, which I have quite a bit to do since it's my first "rail trip" around Europe. Thank you so much for pointing me in the right direction, I really appreciate it.