Hi, everyone! :)  I'm new to RPoL, but think I've got a hang of the basics. I've done free-form RP for years, and have joined up with a GM-directed semi-free game (they have their own behind-the-scenes system that they hide from the players) here and it's going well so far. I do have an interest in getting into more system and rules based RP as well, but really have no experience at it. My question is, how much knowledge of a game system does a typical GM expect? Is it expected that the players have books and a good understanding of the rules? Or will they generally lead the players along and tell them what they need to know? I don't want to spend a lot of time looking into games if I'm not going to have any idea how to play them.

This is going to vary a lot on a case by case basis.  Personally I'm happy to accept players who don't have any previous knowledge and I'm happy to talk them through things, but I'd want them to actually put an effort into learning (even if not all at once).

There is no "typical" GM on RPOL.  Some will happily handhold a gerbil through the process, others expect MENSA-level understanding.  Some will say right out in their game advertisements that they only want experienced players, others won't.  All you can do is be honest with the GM when you apply and see which kind they are.

And realize that just being a GM here doesn't mean that they're special people with outstanding interpersonal skills, so even if you encounter a GM who gets cranky with you for even asking, others won't.  Just keep looking and you'll find a game for you.

Thanks for the info. Guess what I should do then is read the basics on a couple systems and just pick one and try to find a game that sounds interesting and apply. Worst that can happen is the GM says no.

It's also worth knowing that a lot of systems come with different amounts of setting attached.  For example, something like GURPS is supposed to work with just about any game, the ever popular D&D has several of its own fantasy(?) settings and my personal favourite Exalted has a very definite single setting that it comes with.  Of course people might adapt a setting-based system for their own ends occasionally, but you get the idea - different systems are good for different things.  There's also a big difference between heavy and lite mechanics games - whether the system has 4 or 5 stats and one type of roll to cover just about everything, or multiple big books filled with options.  People usually seem pretty happy to discuss their experiences when asked, so feel free to ask if you'd like guidance towards whatever might best suit your interests.

Since I run a lot of RPG events at the Origins convention, I'm used to players at all levels, from "I never played a roleplaying game before" to "I just ran the event at the next table." My response to everyone is the same: "All you have to do is tell me what your character wants to do and I'll take it from there."

Of course, I run Call of Cthulhu, which is one of the easiest systems to run. Also, what I'm trying to do is provide a fun ride in a four hour slot, so I tend to hand wave a lot of details. A lot of people seek out my games from year to year, so it seems to work.

Here on RPOL I tend to run the same way. I guess I do expect people to know enough to roll D100 after a few weeks without my prompting them, but I always set the dice roller to default to D100 as well.

I haven't had to do it for a while, because I'm in several long-running games and don't have much time to add another one, but...

When looking for games, I tend to look first at games with systems that I know.  Given that the last 'new' system I picked up (prior to RPOL) was sometime in the mid-90's, I don't have much success at finding games that way (but it does occasionally happen...or did, anyway.)

If/when that fails to turn up anything that intrigues me, I then start looking for games that sound appealing, even if I don't know the system.  Going that route has been the impetus for learning the basics of five or six new systems.  Just tell the GM that you're new to the system and you'll require a little extra coaching if accepted into the game.  A lot of GMs that I've seen end up doing the majority of the system work behind the scenes, as it were, so you really only need to know enough to put your character together and they'll let you know when they want you to roll something...otherwise, you tell them what you want to do and they take care of it.

If they aren't willing to work with you on learning a new system, they'll tell you...and then you can 'walk away' with a clear conscience and find another game.  There are certainly plenty of options...

Ashleywishes, if you are considering to buy rpg books I'd say you should look online for the whichever system's rules in SRD (System Reference Document). Dungeons and Dragons 3rd edition is available that way for free as is Dungeon World and many others. There are a lot of games that use an Open Gaming License and have their rules posted for use and for game developers.

Also, there are tons of "indie" games that are free to download, play and modify. Using the free versions and SRD versions could save you a lot of money. If you're like a lot of folks and like to have physical copies, then Amazon, eBay and local book stores are your best friends (though I bet you already knew as much).

 Have fun!