Beekeeping is not an endeavor that should be taken lightly and one should make sure they are committed to the time and effort required to maintain a healthy hive. Once you have made that decision, how does one go about becoming a beekeeper?
The first thing I did was try and learn everything I could about bees and beekeeping. There are quite a few good books on the subject, and I recommend either buying or borrowing several to get exposed to variety of techniques and philosophies. I found The Backyard Beekeeper by Kim Flottum and Beekeeping for Dummies by Howland Blackiston to be excellent resources.
However, the best way to learn is by doing, and if you are lucky to live in an area that offers beekeeping classes, it is truly an invaluable experience. Not only does it give you hands on experience, but you will quickly figure out if opening a hive filled with tens of thousands of bees is something you really want to be doing in your spare time.
If you live in the Austin area, there is an excellent class at Round Rock Honey given by Konrad Bouffard. It was this class that really gave me the confidence that this was something I could do and do well.