Freebase Dali

I started beating on desks, counter-tops, and any available surface since I was about 8 years old I think. After that I started making my own drum sets out of my mom's plastic-ware and cookie tins and pan tops and generally developed a sense of coordination and rhythm by practicing along to any recorded music I could find or just by playing along to music on the radio. Eventually I got a real drum set and it all snowballed up-hill from there. Today I would consider myself a very competent drummer, but there is ALWAYS room to improve on musical ability.

Obviously, the key element of becoming a decent drummer is practice. Yea, it may take less time for a person to get "technically" good if they have someone telling them exactly what to do and how to do it, but the real elements involved in what it takes to become a competent drummer are coordination, timing, and a very keen ability to understand musical structure at an instinctual level. This can be taught to a very minimal extent, but the majority of it has to be learned and practiced through action.

The important thing you need to understand is that simply going to an instructor is not going to make you a good drummer in X amount of time. You literally have to create the connections in your brain through practice and understanding. To some this comes naturally, and to others it's more of a challenge. But in either situation, the common denominator is the drummer's willingness and passion to play and practice as much as possible. If you're a weekend warrior, don't expect a significant amount of growth in a short period of time, even with an instructor.
Drum practice should be a daily thing. You have to create an ability in your brain that's a lot more complex than learning how to play tic-tac-toe or getting good at headshots in Modern Warfare 2.
The time-frame at which you'll become good enough to drum for a GOOD band is directly proportionate to the amount of time and effort you put into your trade.
I'm not going to lie... It doesn't happen overnight. It takes years before you're ever even comfortable with your own playing along side an established drummer. Most of us aren't gifted virtuoso's of drumming from birth. All I can say is that you need to invest the time and the effort, and yes, it would be beneficial to get all the instruction you can...
But don't expect that just because you pay for an instructor that you'll pop out the other end a good drummer.

Use the internet. Tutorial videos. Friends that drum a little better than you. Learn their secrets, techniques and methods. Read articles. And most of all, APPLY what you learn VIGOROUSLY. All the time. Drumming should be your life.

The most important thing I can say, though, is don't look for an easy way to become a good drummer. It's not going to happen and you'll waste your time doing so. If being a good drummer is what you want, you better be damned prepared to work for it. Instruction or not.