The first thing I would do is a little research on the agencies. Look into TDI, IANTD, GUE, NAUI Tech, PADI DSAT, and SSI Tek-XR. I am not going to start a debate on DIR vs. the world or which agency is best. You have to make that decision for yourself. But I would take the following into consideration while doing the research:
1) Where can I find the best instructor in the area?
2) Where can I find a mentor in the area?
3) Where can I find other people to train w/ and dive w/ in the area?
4) Which agency will allow me to the do the type of diving I want to do?
I will say from personal experience that it is tough to go down the GUE path when you have no local resources. Imagine investing the time, money, and effort in getting through Fundies and Tech1 to find that you don't have anyone to dive with. This is what led me to TDI. There are some great TDI instructors within an hour from me, the majority of the tech divers here are TDI, and I have a decent sized group of TDI technical divers that I can train w/ and dive w/ on a regular basis.
Once you find out which path you want to take, see if you can tag along on a training dive to see what the deal is. Your diving will have to change considerably to dive at this level. You have to constantly maintain your skills. This will require a lot of time and a significant financial investment. If you like what you see, try to find a mentor. This can be your instructor or a local diver that is willing to invest the time in you. They will help you choose your gear, learn the skills, and will hopefully give you an honest evaluation on what you need to work on before taking the plunge. Once training begins, you should constantly re-evaluate where you stand with your skills, your experiences, and your comfort before moving forward. Tech diving isn't about collecting cards. Even in training, you can be exposed to some potentially dangerous situations and you need to be able to honestly assess your ability and willingness to accept those risks.
I'm still a tech newbie but so far it has been a rewarding experience and I look forward to continuing my training. All I can say is enjoy the journey. Don't look it as a means to an end but as an opportunity to learn the skills and learn something about yourself in the process. Have fun!