You will have to find out on the day, like everyone else.
The Runescape Halloween event for 2008 just came out right now. Date: October 28, 2008. There is a quest too. If you don't believe me go here: http://www.runescape.com/ it's already started =)))))))))))))))))))))))))))))))))))))))=
Have patience, it's not Christmas yet. And by the way, I don't know.
You will have to find out on the day, like everyone else.
This event has already been and gone.
There are some things that are lying around runescape like small fishing nets by the fishing tutor and bronze axes that you can just pick up. other than that you could try asking people for free stuff although that usually doesnt work.
You can get another spider cape by going to Diagno and looking at the holiday items he has.
Try browsing the Runescape Forums "Future Updates" section see if there's answers there.
This is the perfect time of year for find Halloween decoration ideas and advice. Halloweendecoratingideas.net is a great website to get you going with your holiday planning.
A Christmas Warble, some kind of parody of A Christmas Carol. For help, go here: http://gameolosophy.com/games/online/runescape/how-to-do-the-2009-runescape-christmas-event/
Not 100% sure, it will be released closer to halloween, maybe a few days before or maybe on the day. The only way you are going to find out is by keeping a beady eye on the Runescape homepage for the news announcing it, asking for when it is released is a question only Jagex team will know.
The 2009 Christmas event is a holiday event planned by Jagex. It will be released on or before 23 December 2009. It was announced in the update "Christmas Cards and Blog" and in the developer blog "Holiday Event: A Christmas Warble". In conjunction with the announcement and the release of the blog, three Christmas cards were released in the website.The event was developed mainly in September and October of 2009. It is the first project developed by Mod Edam.A new particles graphics effect will be added in the form of snow. It is the first place that players will see this in RuneScape.Mod Ajd has said that the Christmas event will be better than last year's, but Jagex will "leave the players to decide that one."Picture of event:http://images2.wikia.nocookie.net/runescape/images/8/87/Xmas09-ice_sculptures.jpgSource:http://runescape.wikia.com/wiki/2009_Christmas_event
There is a new free player quest out right now, but for a limited time only. Swept Away will be unavailable to free players in a short time after the 2008 Halloween Event. Only Jagex knows when they make quests.