Here are my suggestions- you may get many responses, but as someone who has climbed this hill relatively recently (last couple of years) my comments reflect a path perhaps like yours.
First off I STRONGLY suggest buying this video:
http://tinyurl.com/d5e6s7o Other people like the EJ videos, but for a basic sweep roll, which is the type most often taught, this is the go-to. There are other roll videos, but start with THIS ONE! And watch it 25 times before you even think of getting in your boat.
Next find some quality instruction. Not just any Joe or Jane Bob Kayak. It ain't cheap but like anything in life, it may be cheaper in the long run to go with a great teacher. The OAC has a few, Jared (sp?) is especially good. He is very positive, communicates confidence, and fun to work with. IMHO someone who is an ACA certified teacher will get you there quicker, and leave you in better shape.
Be prepared to have it take some time. Have someone video you trying to roll, that is very helpful to diagnose small problems (left arm punching, seeking resistance with the blade, lifting the head, etc.)
Get some nose plugs, goggles can help too. Did I say get some nose plugs?
Next, watch the video another 25 times.
Then practice until you simply can't stand it anymore, then practice some more. Despite peer pressure don't worry about advanced rolls until your basic roll is 1000% bomb-proof. There will be time later for that.
That's my advice anyway. A good, reliable roll is essential to progress in this sport. No short cuts in time or money to get there.
And a little off-topic, get the very best helmet you can afford and make sure it has a dynamite fit and protects your whole head. Spend much time getting that fit *perfect*. The day will soon come when you find yourself upside down taking those hard knocks. It is the Pacific Northwest way.

George B.