The first thing anyone should do when they unbox their new conmputer (desktops don't come with install media either,) is to create their restore media. Every computer will allow you to make at least 2 copies (some will allow unlimited copies.)
You can also download recovery media from Microsoft:
Windows 7 Media (you will need to enter your product activation key to download it)
You can do a google search to get instructions on downloading the proper media for Windows 8, 8.1, and 10, depending on whether you've got retail or oem versions of Windows.
The downside of downloading recovery media directly from Microsoft is it will be up to you to get all of the drivers you need for your system. If you create the system's recovery media, you'll have all the drivers automagically installed, but you'll also get the standard bloatware manufactures tend to install on new systems.
Finally, if you don't know your activation key (and it's generally no longer on a sticker on the system,) there are a number of ways to get it, such as "Magic Jellybeans" and my personal favorite, because it gives all sorts of system information that can be very useful, "Belarc Adviser."
Mark