As for 4th, there's not too many people with those books yet, and a lot of people still have their 3.5 books, so it's not a problem at all to roll a 3.5 game, especially if you're more familiar with that engine.
I prefer to simply roll ALL the dice myself when I'm DMing a game over a forum. I can just grab an actual die, or a simple click and happen dieroller installed on my computer, not having to worry about having them stored on websites. Elliquiy does have a dieroller built into the forum, so DM's can check if that's really what the players rolled, but A, it can make the game go slower, and B, I have several people that don't even really know what to roll when.
You should set a bit of plot for yourself, making sure to have game equivalents for the stuff that requires dicerolling, mostly combat and traps (If the group is just gonna talk to a peasant to ask when he last heard those weird sounds, then you don't need to stat that peasant out, they're just talking). By this, you should already have an estimated level for the player characters, and as your first time DMing, lowlevel is highly recommended.
Then simply open a post on the players wanted board, and include:
- A simple glance at the plot, to catch players' interest.
- The engine you're using, as well as what materials are allowed and what experience players need (this depends on how much you want to do. If you're fine with helping people make their character, or make their character for them, then they don't really need experience. The SRD ( http://wizards.com/default.asp?x=d20/article/srd35
) could provide the neccesary requirements.
- The type of game played (what board will it be on? Do you want a certain matchup of genders? Are people playing crossgenders ok? etc...) as well as the amount of players you're looking for.
- Character generation rules. Here, it's actually pretty useful to use a point-based system, to prevent players from making a lot of roles that have dire influence on their character. Include the starting level/xp, starting gold, if races with LA are allowed, etc...
when it looks like you're actually getting somewhere, you'll probably want to create three threads on the most appropiate small games forum:
- Characters, where players can post their character. An alternative is having the players PM you their characters and posting them yourself. I like players posting them themselves. With their avatar next to them, it's easy to find the right one.
- An OOC thread (Out of Character) where the players can ask general and specific questions about the game, and have a bit of chit-chat. Informing players that they gained xp/leveled up is also best mentioned in this thread.
- An IC thread (In Character) where the actual story plays out. Your first IC post will most likely be describing the room the characters are gathering in. It's common sense to have all players post once in the thread before you write your first reply, so everyone had a decent chance to make their introduction, but after that, this will no longer be required. Out of combat, (unless you only have say 2 players) it is best not to use a specific posting order, as that will only slow down the game even more.
In combat, roll the initiative for all involved characters (including NPC's) and post a list, possibly with a line marker at the top. You can copy paste the list, moving the line marker around to show who's turn it currently is (it should always be the turn of the person right below the line marker). You can hide NPC's from the list when they haven't made an action yet, or when players are not aware of their presense. Players can actually write their actions in advance, possibly including some IF's. If, by the time it's their turn, and their action no longer makes sense in the current situation, just discard their earlier written action and give them the possibility to write a new action. Most of the time though, you should be able to apply their old action and speed the game up, by dealing with two player actions in one post.
You might also want to look at some of the System games going on on this board. They might give you an idea about how such games are run.
PS. Someone else happened to have a similar question on a different board: http://elliquiy.com/forums/index.php?topic=17188