These are 100% free and working autolikers for Facebook Fanpages. The method they work is the same as regular autolikers. You should use the account that was used to create a page, although sometimes you can type custom fanpage id and it will work as well.
I will update the list if I find something interesting. These are tested&working as for May 2017:
- http://www.cyberlikes.com/page-liker – among the page liker, cyberlikes provides quite nice auto tools.