Dear..I don't think Gtalk directly get's installed to mobile...

The only way out is you have to install mobile softwares like Fring, Nimbuz which supports gtalk,msn,yahoo,sip device and so on..
visit :
www.fring.com
www.nimbuz.com
and download any one...create a new user id...once u login you can activate gtalk or yahoo or msn by providing the username and password...

I am using both ... go for nimbuz,,,it's advanced

Regards