Anakin born and, raised on Alderraan. Before he became Vader last he knew all his family was there and, Obiwan. Tattooine not shown at all. Empire would be around and, the Emperor would only be talked about. Degobah is the meeting place for the jedi as well as the place for all commerce. Vader lead the assualt on Degobah and, thinks he killed Yoda in Episode III.
Where does this quote come from? There is one big contradiction, though: Obi-Wan says in ANH, "...your Uncle thought he [Anakin] should've stayed here [Tatooine]...not gotten involved." He couldn't have been raised on Alderaan. Born on Alderaan, sure, but not raised. So, it seems logical that Obi-Wan found Anakin on Tatooine.
So, there is just no way around this "fact." It had to be that way. However, we don't necessarily need to see Obi-Wan pick up and get Anakin from Tatooine. It could be assumed at the beginning of Episode I. However, I feel it's very important to Anakin's development. It's like the "serial killer" component. You want to see what their background was like, and how they became what they became. It's only normal curiousity, and I feel no different about Anakin. Need to see where he came from, how did he become "Darth Vader."
Never heard the Dagobah as the base for the Jedi thing before.