I have watched weeds tv show. it is very good serial. its every season is fantastic. I mostly watch it online from edogo
You have got so many links here. You can use any of them.
Weeds is a television series which is based on drama . It is created by Jenji Kohan, produced by Lionsgate. it has 5 seasons and 65 episodes. This is a nicde show and you can watch it from Showtime channel , if you will not get any idea from here then you can search it from http://download-tvshows.com
Along with the option given by Rainn you can also Watch season 3 of Weeds from http://weeds.download-tvshows.com/ . Visit here if you want quality.
i have watched weeds all season.http://download-weeds-episodes.edogo.com/here you can watch wees season 3.