Yahoo !

Log into your Yahoo! mail with your username and password.

Click on Inbox or whichever folder you have stored your mail.
Open the mail.

If you do not see the headers above the mail message, your headers are not displayed . To display the headers,
Click on Options on the top-right corner
In the Mail Options page, click on General Preferences
Scroll down to Messages where you have the Headers option
Make sure that Show all headers on incoming messages is selected
Click on the Save button
Go back to the mails and open that mail.
You should see similar headers like this:
Yahoo! headers : Daniel.
Look for Received: from followed by the IP address between square brackets [ ]. Here, it is 202.65.138.109.
That is be the IP address of the sender!

Gmail

When you receive an email, you receive more than just the message. The email comes with headers that carry important information that can tell where the email was sent from and possibly who sent it. For that, you would need to find the IP address of the sender. The tutorial below can help you find the IP address of the sender.

Log into your Gmail account with your username and password.
Open the mail.
To display the headers,
Click on More options corresponding to that thread. You should get a bunch of links. Click on Show original

You should get headers like this:
Gmail headers : Daniel
Look for Received: from followed by a few hostnames and an IP address between square brackets. In this case, it is 65.119.112.245.

That is be the IP address of the sender!!
NOTE:=
This will not work if the sender uses anonymous proxy servers.

Hotmail

Log into your Hotmail account with your username and password.

Click on the Mail tab on the top.
Open the mail.

If you do not see the headers above the mail message, your headers are not displayed . To display the headers,
Click on Options on the top-right corner
In the Mail Options page, click on Mail Display Settings
In Message Headers, make sure Advanced option is checked.
Click on Ok button

Go back to the mails and open that mail.
If you find a header with X-Originating-IP: followed by an IP address, that is the sender’s IP address
Hotmail headers : Delano ,In this case the IP address of the sender is [68.34.60.59]. This is be the IP address of the sender.
If you find a header with Received: from followed by a Gmail proxy like this
Hotmail headers : Delano
Look for Received: from followed by IP address within square brackets[]. In this case, the IP address of the sender is [69.140.7.58].
Or else if you have headers like this
Hotmail headers : Delano
Look for Received: from followed by IP address within square brackets[].
In this case, the IP address of the sender is [61.83.145.129] .
If you have multiple Received: from headers, eliminate the ones that have proxy.anyknownserver.com.