Im not sure if you guys even code in Visualbasic or python or what, but the code is pretty generic. And its open source so your welcome to edit it, too.
You cant hack steam accounts unless they login threw the Steam webpage. If they use the program steam to login it wont work because they have encrypted it stealersdont record there keystrokes. you could use a keylogger if you can find a good once, I cant be bothered to post any at this time. Once there is ill post it. Not even stealers can get them unless like i said they use firefox and login via steam website. Sorry
Steam stealers do exist. There are fake programs and DNS poisoning that allow this as well as phishing and pass stealers if users log into the community.
You cannot "hack" steam. Steam is just a interface which allows users to purchase games from the publishers as well as talk to friends and other users across the globe.
If you wish to play "tons" of games you can try to get a cafe account which will have loads of games on them.
If you wish to not play the games online, you can download them from torrents/warez sites and play offline or online(non steam). However, this is "illegal".