Depends on how much of a beginner you are, when I started out, I found one of the hardest things to do was to change from one chord to the next and have it sound clean and quick. Playing often is also important, try for atleast 30min a day, but also try to squeeze sessions in, even if they are only 5 minutes, it all helps.
This site (guitartricks) has lots of good excersizes on it, so maybe try them. also look at http://www.guitar-pro.com and download the demo version, it is a tab progarm that has musical notation and tab, and also midi playback options, so you can hear what the song sounds like, on this site there are links to many tab sites for Gp tabs.

Keep playing man, it is never too late to start, and with enough jamming you will get better.
One more thing, there will be times when you feel as if you have not progressed for months...I call these droughts...stick through it, you will always wake up one morning after a long drought and sudenly be much better

Welcome to the greatest hobbie on Earth