I'm going to add that it is very important that you have tools and a place to work on your car if you're going to embark on a project.
I'd say for the most part [Well, at least for me] we are into Zs because they are plentiful, cheap, and stay cheap if you work on them yourself. They're no Porsche or Miata, but for what you can do to them, for the money it's a great deal.
This is a great car to learn on, it's really simple and this site is great for upgrades and technical advice. I'd never done any modifcations to a car before I got my 280Z.
Good luck with this, take your time and do your research before you buy a car. If you do it right and keep the proper mindset than it will be a great for you.