Re: Utterly new....and ready to get going.
In reply to Vase (msg # 1):
Hiya Vase, and welcome to RPol.
The answer to your question is almost as complex as the question itself, but I'll give it a shot.
TTRPGs (Tabletop Rolplaying Games) are played in one of two ways: With a mechanics system or without.
The "with" versions are things like DnD, FATE, Call of Cthulu, Anima, etc. and tend to be classified as either 'Dice Systems,' where at least a portion of the game calls for rolling dice in varying numbers (like 7 six-sided dice, abbreviated 7d6), or diceless, where there are specific rules and perhaps even stats, but no dice are actually rolled (Amber is the only example I know of).
The "without" are typically called 'Free-form.' Free-form simply means there are no established stats, and typically only the bare minimum of rules (things like: you can't post the actions or reactions of another player; you may not change the weather; etc.).
On RPol (or at least form what I've seen) there's a healthy mix of the two available.
If you're looking for the 'traditional' tabletop experience (a.k.a. Dungeons & Dragons) then you'll need rulebooks, and typically someone to help you out with the system (and there is a lot of help available here ;), no worries about that). If you prefer free-form, then all you need are the rules of the game.
tl;dr: If the game is using a particular system, then yes, you should get the books and do yourself (and your GM) a favor. ^_^