~ってから shows "one after another".
行ってから means "after I go".
~ったから shows "cause & effect".
行ったから means "because I went".
Note that 行くから is also valid, which means "because I (plan to) go"
To answer additional question added by OP:
I'm going to buy the book because I'm going to America.
-> You buy the book before you go, and you buy it because you are going.
I'm going to buy the book after I go to America.
-> You buy the book after you go. The reason you buy the book may not be related to you going there at all.
I'm going to buy the book because I went to America.
-> You buy the book after you went, and you buy it because you went.
Note: in 行ってから本を買う the location where you buy the book can be in America or after you return back to your place. You may need to use specify あそこで to show that you are going to buy the book in America, or use 行って来て to show that you are going to buy it after you return home.