Question on behavior, sometimes he is really reluctant to step-up and be handled, I'm assuming the best way to help him be more social is to handle him. Any other tips for that? Also I would like him to be more friendlier to strangers, what would be the best way to go about that because right now whenever he sees someone else besides me he gets really shy and looks like he is going to bite but never actually does.
Ok, "YES" is the short answer here, but there is a whole lot more to this ... it's great to see that you want to integrate Harvey into your family so quickly

but I really think that you need to give him some space for a while.
You don't know what kind of home he came from - was he handled everyday, was he left in a cage ... maybe he is just a type of bird that shies away from human handling ... was he ABUSED? This is a very precarious situation you are in, one wrong move and you could lose your very young, fragile bond with Harvey.
Handle Harvey on his terms
for now get used to each other, let him get used to his new surroundings, let him learn to trust you, and you him. Amazons don't necessarily need CONSTANT handling, and just like humans, some prefer to be left alone more than others.
I would suggest small amounts of handling time, for the next few weeks. 10 to 15 minute intervals every hour or so. Then as you start to build up trust with him, extend those outings. A great way to interact with Harvey (and to do some training with him) is ladder drills, step-ups, step-ups, step-ups and reward with as much praise as you possibly can, and a treat isn't going to hurt - my boys like ALMONDS but find something that Harvey goes crazy over, then he can associate time with you as good time and something that he wants to do. This should help.
Yes, exposure to more people will help to socialize Harvey better, but let's not run out and introduce him to everyone you know tomorrow. Again, here, small steps work best. Let him get used to his new home and his new human, he's already been through a traumatic time, lets not make it worse by mixing in even more people.
You said that you got his new diet today, please make sure that you are closely monitoring what he is eating, and that he is eating. Sometimes parrots will not take to an instant change in their diets. Please, offer a mixture of food items that are parrot safe for him to try ... the most important thing here is to make sure that he is eating and drinking regularly.
I am going to sneak a peek at this little guy now, and I am even going to copy your link into my post that way it's an active link....
Everyone here's Harvey:
http://i74.photobucket.com/albums/i263/XBStAlKeRXB/untitled.jpg
He's a cutie, but I think that you might have a Yellow NAPED Amazon there, Yellow Crown Amazons usually have red/orange on their shoulders and Harvey looks like he is all green in that area. Not that it matters at all he's still a great looking bird!