My understanding of it, based on The Last Thirty Days: The War Diary of the German Armed Forces High Command from April to May 1945 and Cornelius Ryan's The Last Battle, was that the actual mechanics of the German collapse prevented this from ever happening. By late April of 1945, the final week of the war, the Allies were still over 120 miles from Berlin, where the Russians were fighting. Kesselring's entire army group still guarded the south, to the west of the Czech border, and the Americans were primarily concerned with what they thought would be a fight to the finish in the southern part of the country, the "Redoubt."
The Germans were definitely getting sandwiched, but I don't think there was a point where they were in fifty miles of each other during the actual fighting. The meet-ups were after the fall of Berlin, and were largely ceremonial affairs.
This map gives an idea of where the forces were when the war was ending
Yes, in Amstetten, lower Austria on May 8, 1945 (the last day of the war in Europe), Wehrmacht forces waited on the main square to surrender to US troops. Soon after, American forces arrived and started negotiations.
At this point, a Soviet aerial attack directed at the German troops happened and US and German soldiers ran for cover together.
Source: Portisch Hugo/Riff, Sepp: Österreich II. die Geschichte Österreichs vom 2. Weltkrieg bis zum Staatsvertrag. Munich 1993
I can't give you a page number right now as my colleague seems to have stolen my book. But there is a series of photographs by a local, documenting the meeting and the aftermath of the attack.
EDIT: Found another source in Google books. With the photos! See p.58f
