Welcome to the forum, always good to have a new "fanatic in the making" around
You question is a little like how long is a piece of string. You need to consider what you want, original or modified, how often you plan to drive it for considerations like disc brakes and seat belts and what your own abilities and budget are.
The big kller is usually rust and if you are not able to do rust repairs yourself, having rust cut out properly and repaired using new steel is usually much more expensive than your run of the mill mechanical repairs. Rust is often hard to spot to the uninitiated and you really need to have a look at some memebers cars and let them share some experience with you first if you don't want to get burnt.
I would suggest that your first stop should be to attend a local meeting - although I guess you have a bit of a drive from Newcastle or a club event. That way you can meet some people and they can show you their cars and some points of interest to look out for.
Good luck,
Burnsy