Download it from here and extract LatoOFL.rar then go to TTF and open this font-face-generator click at Choose File choose font which you want to use and click at generate then download it and then go html file open it and you see the code like this
@font-face {
font-family: "Lato Black";
src: url('698242188-Lato-Bla.eot');
src: url('698242188-Lato-Bla.eot?#iefix') format('embedded-opentype'),
url('698242188-Lato-Bla.svg#Lato Black') format('svg'),
url('698242188-Lato-Bla.woff') format('woff'),
url('698242188-Lato-Bla.ttf') format('truetype');
font-weight: normal;
font-style: normal;
}
body{
font-family: "Lato Black";
direction: ltr;
}
change the src code and give the url where your this font directory placed, now you can use it at your website...
If you don't want to download it use this
<link type='text/css' href='http://fonts.googleapis.com/css?family=Lato:400,700' />