Tips for a beginner in collecting a set of Roman Armor/equipment

[Crispvs]

I would concur with what John and Evan say. Added to that, if you wanted to concentrate on the third quarter of the 1st century AD, as most groups do (which would allow you to join in with other re-enactors more easily at a later stage if you wanted to), I would humbly submit my own thoughts on the matter, which can be found in this thread from last year:
http://www.romanarmytalk.com/rat/thread-27514.html

I would agree with Evan's comment though, that you may need to think about the cost of books (and photocopying) before you start getting yourself expensive pieces of Roman kit. That said, I hope it all goes well for you.

Crispvs