My friend does (see post above) he is now good to the point where he never has to buy anything because he wins boosters from drafts. It took him about 2 months to attain that level. Though he is one of the best constructed players around his limited game only came good after lots of online magic.

If you're not good at magic to start with, online will be pretty daunting, most people on there know what they are doing as they are happy to pay even though they will probably never get the cards off the site(you need a full set)