As someone who recently came over to planted tank land - it's information overload. There is just SOO much information, you literally can't keep up.
Read, read, and read some more. Then ask questions. Then question the people who answer you, because there are a lot of nice people with old answers that are not so true any more (for example, look into why watts / gallon isn't good advice anymore when dealing with how much lighting you need for your plants)
I would suggest reading up on one aspect (perhaps lighting - this is where I started my research) and getting fairly comfortable with it. When you start deciding what plants you will want, that will determine how much light and fertilizers, and such - but it will sort of grow from there. (worked fairly well for my anyway - I feel like I have a decent grasp on the basics)