1) I have a product to sell that also requires an annual subscription. Should I set this up as two products, with one being "required" by the other? Or should I set this up as one product? Also, the doc says the recurring billing starts the same day of the purchase...I would like to include the 1st year in the initial purchase immedieately, and the recurring billing will not happen until one year later. Is this possible?
I would set it up as a required product. The feature that you are requesting about waiting a year to bill the user on annual subscriptions is called trial subscriptions. We have built that feature into our registration pro module you can see the module setting http://www.smith-consulting.com/products/dotnetnukemodules/registrationmodules/registrationpromodulesettings.aspx
Recurring billing starting the same day of the purchase is the way normal Authorize.net arb transactions work. We would need to add trial subscriptions to achieve what you want.
2) How are "virtual" products handled (ie, an annual subscription)? If someone is just purchasing a subscription there is no need to get a billing address or ask for shipping methods, etc. But I cannot figure out how to disable these steps for this type of product. I figured it would be handled like a downloadable product, but I cannot get that to work either.
If you check “free shipping” in the cart settings it will hide the shipping info on the cart screen.
3) I have checked "combined shipping and handling". But in the "Ship Method" drop down the price doesn't include the Handling fee, only in the summary. I think this is kind of confusing - shouldn't that price include handling too?.
The combine shipping and handling checkbox will only combine shipping and handling on the cart screen and confirmation page it doesn’t combine it in the shipping calculator. Your right it could be confusing I will add this to the dev list