Marlin and IZH
Two choices that I know of (looked into it three years ago).
1. For the true novice, the reccomended rifle is a Marlin bolt action with the optional biathalon package (includes magazine rail etc.) You'll probably have to find a dealer to order it special. Very accurate and a good starter gun. Marlin used to be a major sponsor.
2. Go to the IZH Baikal web site and have a look. There rifles have won about as many medals as the Anshultz stuff.
3. The used market (have to go to a biathalon club to find these).
Of course you'll need skis and physical conditioning most of us only dream about
JPM