I have not seen a forum just for titanium users only. There seems to be more users out there that love HTC Sense more then titanium.
I have the weather plug in installed on my device. When I set it up I highlighted the plugin and clicked the menu soft key at the bottom of the screen to. Then I updated the zip code and disabledthe auto updates. You have to change the update interval and forecast update interval to 0 to do that. Then I clicked on save/exit and exit without updating. Then I click on the weather pluggin to update the weather.
here is a forum that has many diffrent plugins
http://forum.xda-developers.com/showthread.php?t=511052