There are a lot of Freeware programs for the Palm OS. Check out
Freeware palm. They seem to have a big selection. Also, we have a
Software Store that features thousands of applications and utilities -- of which most are available as a free trial. Just don't be like me.. When I first got my Treo 600, I loaded up all the free trials and it didn't allow me a opportunity to properly trial the software.
A few titles that are worthy of your new Treo 600.
SnapperMail : A simply fantastic email client and very Treo friendly including support for the 5 way nav and more. I've been using Snapper for years and it's great.
PocketTunes : If you plan on playing MP3's, this is a great program. The deluxe version allows you to stream radio via the Treo which is very cool. You can find streams at
TreoMobile Butler : This is a swiss army knife of Treo specific utilities.
Call Filter : I use this specifically as a Ringtone Manager, but it's actually much more robust. It can direct calls and allows you to set up different rules for groups, individuals and more. It will allow you to set up MP3's as ringtones, but this requires PocketTunes for this functionality. One note, it's incredibly stable which can't be said for all ringtone managers.
There are others... but these are my favorites.
That's it for now. There are lots of games, productivity tools and more. It's endless. Have fun!