If you don't want to sync v1 and v2

[lizard]

The easiest way to start using your existing OmniFocus database in OmniFocus 2 is probably to sync. But, if you’re not syncing your OmniFocus database, here’s how to copy your database manually:

1. In OmniFocus 1, Command-click on the main window’s title. This opens
   a little drop-down. Select that top folder named OmniFocus. This
   will open a Finder window with your OmniFocus v1 database in it.
2. Repeat step 1 in OmniFocus 2.
3. Quit OmniFocus 2.
4. Copy the file found in step 1 to the location found in step 2.
5. Launch OmniFocus 2.