System.Data.SQLite missing?

[Bobson]

I'm not sure what happened - I thought I wrote a post, but it's gone now.  Apologies if this turns into a double post.

I'm trying to build a MonoMac application (eventually to share the database with a MonoTouch app) using Catnap as the ORM.  However, no matter what I do, I get one of two errors:

Unhandled Exception: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.DllNotFoundException: System.Data.SQLite.dll

or 

Unhandled Exception: System.IO.FileNotFoundException: Could not load file or assembly 'System.Data.SQLite' or one of its dependencies. The system cannot find the file specified.
File name: 'System.Data.SQLite'

Clearly there's something wrong with my System.Data.SQLite, but I have no idea what.  I've tried using references to System.Data.SQLite.  I've tried using references to Mono.Data.Sqlite.  I've tried fiddling with .config files.  I've tried copying the .dll or the .dylib directly into the build folder.  I've tried all the above in various combinations.... Nothing.

Can anyone tell me what I'm doing wrong?  Or how to get past this?  Is it just my install of Mono that's broken?  Do I need to install something else?  Is there anything else I can try?