I have a case of writers block for an adventure/campaign that I am writing and I wanted to know what tools (websites w/ guidelines etc.) you use when creating an adventure/campaign. Do you use published adventures or do you write them yourself? Any advice would be appreciated. The campaign is going to take place in Eberron in case that helps.
I ran a Dragonlance campaign in college but since then, I have used my own settings. I can't provide guidelines, or method to my madness. I am also not too familiar with Eberron, so I'm trying to sneak in under the "any advice is appreciated" category...
My last campaign was based on Irish/Celtic myth. I took an elective class in college and really enjoyed the literature. And, you know, it was a "Setting" complete with feats, outer planes, fey, magic items, powerful spellcasters, druids and warriors, etc. etc.

I read more books related to it, surfed the web for translations of the old legends, read up on bronze age cultures and history, etc. etc.
So essentially, a lot of homework and research coupled with giving everything an original "twist".
I developed a world which was "low magic". Arcane casters had been hunted down and all but wiped out centuries ago when they had been equated with a race of evil Illusionists that fought for dominance on the main continent (the Fomorians, only loosely based on the myths). The "old gods" of the original people (the Tuatha de Danaan) had also slowly been waning in power, having been replaced by worship of more recent ancestors. These ancestors essentially represented 5 warring clans - this divide made it all but certain that the humans coudl nto come togetehr and worship the Elder Gods (the providers of true clerical power).
The only neutral parties left were the Druids and they had sort of "devolved" into mainly an expert class. So the PCs challenge was to return the balance of magic to the world. Along the way, dark forces (The Triumvirate - a group of Medusa spell casters from a distant land and roughly equivalent to the Roman Empire that ultmately ushered out the era of the Drudis in real world) that had an interest in keeping the continent "low-power" awoke the Giants of the Giant's Stair (Northern Mountains - roughly equiv to vikings) to make war on the humans before they could succeed in returning to their old glory.
Anyway, too many years and too many stories to share, but you get the drift - it was based on real world mythology and extrpolated into a new world. New names, different history, etc.
I've got a new campaign idea in mind which comes from just mainly twisting around current events. It's sort of a cataclysmic idea where a world is actively being rent apart between the various elemental and transitive planes (sort of a play on global environmental problems - and no I'm not looking for a global warming debate). However I often thought a fun way to run a campaign would be to make a world that was very loosely connected to the Real World (say America roughly corresponds to a fantasy realm of which is a republic of city states for instance) and use current events to fuel your ideas.
So, I don't create from whole cloth (which is often what leads people to writer's block) but seek a foundation for inspiration...
I do have shelves full of old modules / setting info, but it's mainly for scavenging purposes (I need a map, check - I need a city - Ahh there's that 2e Lankhmar module...)