04-14-2009 07:56 PM
Hi and Welcome to the Forums!
All of the alerts can be accessed via the Sounds app. In portrait and with the limited list of icons showing, at the top left, below the battery level, there should be a square icon with a little speaker in it with sound waves coming out of it. Click that to pop up the Sounds app. Scroll down to "Set Ring Tones/Alerts" and click that. In there (some collapsed with + signs -- click to expand) are all of the apps that use sounds for alerts and such. Somewhere in there should be Google Talk and you should be able to adjust the alert from there.
BTW -- I've never used Google Talk so I can't say for certain that it'll bein the Sounds app...but that's the logical place for it to be.