At present I know of no way to transfer data to your Katana except for vCards. As far as I've been able to determine, Sprint cripples the ability to do this in their phones to force you to subscribe to their services.
Your best hope will be to follow the progress of
BitPim and hope that its developers eventually support the Katana.
If you want to download ringers to the phone, you will need to get the audio into a Qualcomm Pure Voice (.qcp) format. Qualcomm has a free utility to do this but it runs only in OS 9 and "support for newer Mac operating systems is not planned." Download it
here.
Most of what I've learned about my Katana I read on the
Sprint User's forum.
Sprint's strategy seems to be if you want to transfer data between your phone and your computer, they want you to pay them for it. I hope that my contract with them runs out as soon as an iPhone is announced (and that Cingular works in my area, if they in fact turn out to be the carrier).
PB Ti 1 GHz; PB 17 1.33 GHz; iMac DV SE; iMac D, iPod mini Mac OS X (10.4.7) Legacy (Appletalk) networked printers