Tips for a beginner: Get a tutor.
Really helpful, they work with you, get to know your style and see where you need to improve. True some of the greatest guitarists are self taught but they are really great and excel your learning a lot.
While we are talking about software I use guitar pro. My teacher gave this to me but you can just as easily download it yourself. If you are not willing to pay or don't want to do it illegally power tab is good. I used this for a long time.
Theory also is very important if you wish to start improvising. It is essential if you want to play jazz.
Easy ways to start improvising is to download a blues backing track and learn the minor pentatonic (the easiest scale of them all). Add in the blues note (in the key of A it is the D#) and just have fun. Or do what I did and just listen to a whole song and just try to solo over it. If you have a tutor you should get to a stage where just the two of you can just have a jam session. Do this with your friends too though it helps to play with someone more experienced than you.
Perseverance is the key.