You need to be specific, what kind of IPs you want to pull?
Website IPs? Or user IPs?
For website IP's the most basic state command you can use on your terminal is "ping
www.website.com", it will reveal you the website IP if it does not have any protection over it. If it does, you will need to use a resolver, which the internet is abundant about, just give it a google search. This are basic tasks for your level which you can do pretty easily.
If you wish to grab user IP's, it's a different story. You will need to be able to make the user "touch anything" that you want him to touch, for instance an URL tracker or my software (Device Tracker, which you can check on my threads). Other than that, if the user has Skype or any other social communication which has avaliable resolvers you could use that aswell. At last resource you will need to do some Social Engineering.