All right, you've got your basic campaign level.
Now, roll 3d10, and consult the following lists:
1
amsel
2:Prince
3:Pauper
4:King
5:Princess
6:Quenn
7:Baroness
8
ragon
9
ruid
10:Wizard
1:Kills
2:Eats
3:Kidnaps
4:Rescues
5:Inconvinences
6:Subverts
7:Controls
8:Replaces
9:Unleashes
10:Marries
1
amsel
2:Prince
3:Pauper
4:King
5:Princess
6:Quenn
7:Baroness
8
ragon
9
ruid
10:Wizard
Then make a plot out of the three selected words (or fill in your own list; that works too); these are seeds; for example:
2,9,9:
Prince Unleashes Druid
Then spin a situation off it:
Let's see... how could a prince unleash a druid? Perhaps...
Local Prince of the realm decides he wants to boost the farmland under his control, so he can support a larger army to either conquer his neighbors or keep from being conquered himself. To do this, he cuts/burns down an ancient forest bordering the lands he controls.
This forest "just happened" to be held sacred by some powerful (read: 1 to 3 levels above the party) Druid or other who takes offense, and takes revenge (packs of wolves attacking the villagers trying to plant crops, locust swarms eating established crops, that kind of thing; doesn't matter that the Druid doesn't have the right spells on his list to cause it directly - perhaps he trains wild wolves to attack, rather than summoning them (although he may do that, too), breeds the locusts by planting the right kind of plants and carefully placing grasshoppers in them at strategic locations, et cetera - DM artistic license, here).
The Prince, seeing his country getting severely hurt, calls out for help.
This is where the party comes in, to react as they may. Of course, at first, they only hear the prince's side (he's the one that called them... but you could reverse that) that something is eating away at the locals (wolf packs, locust swarms, that kind of thing) with no particular reason as to why now. If they dig, well and good; if they unthinkingly run and slay, well and good; can run with it either way, really.
Simple example, but you get the idea; if you take the time to make longer lists, you can use larger die - d12's, d20's, even d100's
Note that this is just a simple technique for a creative aid - it's for when you are running a little short of ideas - and that if you have a plot you want, go for it.