Hi VaScubaGirl, you probably won't get the sort of answer I think you're looking for on here. I'm headed the same way you are, although I don't have as specific a goal as you. I think it's good that you have an ultimate goal like the Doria, it provides direction and purpose, it will help to keep you on track. I've no doubt that you have some smaller benchmarks laid out to check off on the way. Just read through lots of threads here and on the deco stop, I think you'll get a good idea of what sort of things are involved as far as training and gear are concerned. Oh yeah, find yourself a good instructor, people will consistently tell you that's the most important part. You should have no trouble getting names if you ask for them.
I know you'll find lots of great info and advice between those two sites anyway, I have. Good luck, and dive safe and often, if you're anything like me, there are lots of dives between today and the Doria.