welcome welcome to CS, I am sure you will love it here.
Sharing the same IP adress is not a problem as long as you trade fairly between you.
Be sure to read the FAQ here on the forums top buttons, right next to your logging tab, its helpful. If you have any questions feel free to ask any of us Newbie Helpers, our names are in salmon color.
you can check this links also:
must read topics for newbiestips for newbiesHave fun!!