What Are The Official Rules for Carcassonne: The River?
Lance is right on the starting tile -- according to the rules (emphasis mine):  


  Remove the special starting tile from the game.  Instead, begin the game by laying the spring that starts the river.  Set aside the lake tile and shuffle the remaining 10 river tiles face down and draw from these before drawing from the tiles from the normal game.  These tiles are played and followers may be played as in the normal game with one exception: a river tile may not be placed so that the river makes a "U" turn.  Followers may not be placed on rivers.  Once these 10 river tiles have been played, the next player plays the lake and then play continues with the normal tiles.


In regards to the Source and Lake, we've always played that they connect in all directions.  The following links seem to back this up:

According to the PDF rules from ModernJive:


  The statement from Hans im Glück is "Officially, the farm goes around the spring. So it is a connected farm. I personally prefer to use it as a division, since otherwise, despite the river, there is still only one large farm."


And then from Carcassonne Central is this (although the confirmation link in the thread is no longer valid):


  Yes, officially the farm does go around the spring.