Any good online sites for learning acoustic guitar..?

so i've got this acoustic guitar as a gift frm one of my frnd and i really wanna give it a try so if u guys know any of the online sites that provides tutorial for learnin guitar plzzz help me out here..and i cant get a tuner for time being so are there any methods by which u can tune ur guitar without a tuner..any help will be appreciated..thanxxxx