Hi Fred
I received my visa for usbekistan in Frankfurt and it was no problem at all. (for visa issues you need the consulate and not the embassy, so Frankfurt is the right place to go).
We did it via mail and received the passports back after 3 days (on their homepage they say it'll take longer but ours was really quick) so if Frankfurt is not really on your way you can use this option (if you need help just write me a personal message and I can ask some of my friends to assist you with that)
As we needed to send our passports for other visas away we did the Usbek Visa 3 months prior to entry and it was no problem. You have to fill a form in which you write your entry date and leave date, this is then what they write in your visa. The only problem is, when you arrive later than the given entry date you don't have 30 days visa but less. (not like for the china visa where you have 3 months validity and then 30 days visa from the day of entry)
You can find the form on their homepage incl. all information (sorry but German, Usbek and Russian only):
http://www.gk-usbekistan.de/DE/visa.aspGreetings from Lao
Anne