There are several ways to learn guitar tabs.The internet is one way with all the various resources it offers.
For example you could download a guitar course as in the blog resource box,at the page side.
Another is to do as I do and research various sites and content.
An alternative way would be to friend a relative or friend to teach you or I suppose just 'pick it up' as you go along and be self taught.This could be from watching your idle play and starting by copying the sounds.I suspect the latter would be frowned upon by respected players.
Malc.Learn to Play Guitar