Peter,
What lab do you use? Many labs already have interfaces for AC.
When I order a lab in AC, I make sure to have a diagnosis already for the patient. I then select which labs I want ordered (we have some custom lab orders already set). All I do is hit the print button. From there you can hand it to the patient to take to the lab (we draw most of our labs here for the patients).
The lab we use currently is working on their interface, so currently all our labs are faxed to our office. We use UPDOX to import them into the patient chart. Many on here use Paperport to import items into AC. I like UPDOX as you can make custom categories for imported items but it does cost money.
Once items are imported into AC, they can easily be viewed in the "Imported Items" area.