Hello all!
let me introduce myself in a word or two: I am currently dealing with the Gemeinde and the Zivilstandsamt about my binational marriage. When I saw this post I just had to register..

a fun forum you have here!
@itinerant: what you're saying is very important, go to the Gemeinde, the Zivilstandsamt and talk to these people.
They have a so called "Ermessensspielraum" that means they can decide how hard they make it for you to get everything. Once you go there two or three times they usually become humane. DON'T go to immigration or Ausländerpolizei, those folks are payed to keep you out. (Unless you have to of course, but they're less than helpful)
The biggest problem with the visa for preparation of marriage is that the Immigrationsamt decides if they want to give it to you. There is no right to get one as such. But in the end they have to give you a visa to get married, given you are allowed to do so.
Well, in the end all the talking to the people in the Zivistandsamt and Gemeinde is very useless the very instant the entire case is handed to the "Aufsichtsstelle" for rechecking. I received a letter basically saying that the documents are useless and that I should send them back to get the proper stamps on it. Two calls and days later it turns out that the responsible person simply hasn't checked anything but just sent it back to me.

And since I live in a cow town, of course I even happen to know the son of that one

I have to tell him to say hi to her once this is over..
So to sum things up: talk to Standesamt as soon as possible, you need their letter stating that you have given them the necessary papers. Afterwards it's a piece of cake, given you happen to have a police clearance on you. Go to the Gemeinde, fill out two forms, give them a passport copy and that's it!
You do NOT have to be abroad to decide to get married. However immigration doesn't help you if you are not getting married within the limits of your visa. Once you're married they have to accept that. There is no law saying you have to go back for that!
Well i hope that in the end we pass the watchful eyes of the Schweizermacher, you have to see this movie if you come across it by the way. Very old but still (again?) very true
Good luck to all of you!
Rahip