I always get these junk emails in my inbox about some company has transferred money in my bank account or that I have one the lottery in another country, or I have been given a will by someone. All these emails require me to give them my full name address and phone number.

I just want to know where these emails come from and how do they obtain people’s email addresses? Are there any way to combat this? I use spam on yahoo email address but still I get these junk emails. Is everyone else getting them or is it just me? Thanks for your time and sorry for the long explanation.

I believe most of them orginate from Nigeria. Spammers get addresses in many different ways including making them up. Every one gets spam at one time or another, but you can fight it:
You can not completely stop all spam, but you can help to put a big dent in it.
First, try not to open any of them, that only makes them send more and more to you.

Check mark them and click on ‘Spam,’ this should stop those addresses from being delivered to your inbox.
Use your spam filter and block address.
Look for the ‘Options’ link at upper right corner of mail screen and click on it

Options/ mail options / spam preferences
make sure spam guard is on, click on save changes

Options /mail options / blocked addresses
Enter the E-mail address you wish blocked and click on ‘add block’
you will never get mail from that address again.
This should help you to control your spam.
Other tips:
Never open E-mail unless you are absolutely sure who it is from.
Never give out your personal information to anyone.
If at a website and you must sign up for something, check the entire page to make sure you uncheck any lines wanting to send you notices, info, or ads.
Hope this helps.