For the very first steps in python the interactive tutorial at http://code.he.net/
is quite nice.
As always when learning programming the best way is to do some actual programming. Set yourself a simple goal what you would like to program and then code it. Your code will probably suck a lot (especially if you have no knowledge about algorithm design, data structures and such) but if you have a good book you should find a lot of your beginning mistakes and be able to correct them.
Also the difference between Python 2 and 3 is not that big at all. There are some quite big internal changes that makes porting code not trivial, but if you can program Python 3 you also can in Python 2 and vice versa. You might have to look up some API functions that are different, but you'll have to do that all the time even when using only version 2.
What I really really think is important for any beginner to programming (as opposed to someone who can program and just wants to learn a new language) is to read about algorithm design and data structures because that are very important things in every program.
I cannot suggest you a good book because I learned most about that at university and in Java and deepened my understanding with the great "The Art of Computer Programming" by Donald Knuth, but that is a bit too heavy for a beginner IMO.