Usually people use contacts in some app or program. Like for example you may have those in Outlook on Windows 7. Or windows contacts. (Google "location of windows contacts on Windows 7")
If you do have that - you can then sync those by using itunes, quite simple actually.
If you don't - you may have contacts on another type of phone - then you can research how to transfer those.
There a few other ways as well. But if you like typing those, just set up icloud on ipad. Go to icloud.com on your pc, login
open contacts app. Click plus sign and type and save, type and save......