1. Yes, you can play a game just with the Revised Core Rulebook. It has all the rules that players need to know, plus a Gamemaster Section (including how to be a GM and build bad guys).
2. Since you've never GM'd before, find some pregenerated adventures.
Here's a link I found with a list of adventures. Unfortunately, most of the links don't seem to work. But if you have the adventure names, you should be able to find them elsewhere.
Something that I did as a new GM is I found adventures that could logically go together and linked them. "Steal of a Deal" and "Put Up Your Dukes" are a pair of adventures using the same antagonists. You can also link other adventures to them simply by switching out the bad guys.
I personally recommend "
Rendevous at Ord Mantell" (Rebellion era). The heroes meet a gal who need to get her ship back (it crashed in the wilds). The conclusion of the adventure can put the heroes in touch with the Rebellion.
Here's a
link through the Wayback Machine that has a full archive list of Wizards stuff. Several adventures, plus Jedi Counciling articles clarifying rules (and of course you are free to come back here and ask more questions. Feel free to send me a message anytime you might need help).
If you feel up to it after running a few pregens, try writing your own adventures. The pregens can only take you so far, but that is their point: to get you started and help you figure out what your players want to do.
3. Ok, other tips.
First and foremost, talk to your players. Find out what sort of characters they want to be, and then find out what sort of adventures they would like to do. Nothing is worse than trying to force a bunch of blaster-slingers to be a diplomatic envoy during an adventure. You want the players to have fun, so make sure you run adventures that will cater to their style of play.
Second, make sure you are familiar with the game and the rules. If you don't know an obscure rule, that's ok, you can find it later. Just make sure that you know enough to keep the game running.
Third, take the time to explain the system to them. Some of them may already be familar with d20 in general, but the point is you want to clarify basic rules and how the game runs in general. That way everyone is on the same page when you start.
I'm a very involved GM. I sit down with each of my players and help them build their character. That way we both know what the character can do. Sometimes I even have them write character outlines (a great way for the player to get to know his character). Anything you can do to help your players get ready is good.
Alrighty, I can't think of much more right now, but I'll do some more digging and post later.
