are you attempting to gain access to someone's web based e-mail account, or a home program, (outlook, thunderbird,...)

here are some tips anyway...

*If you see an "program" that claims to hack accounts, but you need to send them your e-mail address and password, it's bogus. (don't laugh, I had a friend who wasn't to savy and accidentally did this)
*The only way a program could gain access to an e-mail account (web based) would be though some sort of exploit that would most likely be fixed by the time you got your hands on the software.
*When you cannot gain what you need remotely, your best bet is to get physical access to the machine. You can set up key loggers, run a live-linux distro on CD, aquire windows password hashes,..whatever you need to get the job done.
*There is no magic program.