To Siege, Or Not To Siege? That Is The Question!

As I spoke of in yesterday's post, one of the ideas put forth by the group to settle the matters happening in Bugbear Falls was to put an elite strike team (them) in the city, and have a force besiege to create a distraction, letting them have easier access to the inner bailey, and thus, the keep.

Now, I'm not one to hinder my player's options, so if that's what they want to do, and they come up with the means to do it, then more power to them! However, one thing that I am, is inexperienced with running anything like a siege.

I have, in the past, ran sessions that included mass numbers of combatants/troops, but those were ran with large-ish skirmishes instead of actually running military-like confrontations, with squads, battalions, etc.

I've tentatively looked into the rules presented for mass combat in the Miniatures Handbook and in Heroes of Battle, but need to read further to fully grasp what they entail. I also have a copy of 2nd Edition's Combat & Tactics, but something in the back of my mind is telling me that that way lies only complexity. Having said that, and though I am running a d20 based game, I am certainly willing to look at other system's rules or suggestions for mass combat/sieges.

Maybe there's something out there, perhaps even something I own, that I'm overlooking.