Hi Rachel,

Yes, you can now apply tags through the aweber/Paypal integration. It was not available until recently but it is now, so it's a muhc better way.

You can send emails based on tags, but the way you do it is to create a segment first. You create that segment based on tags and then select it instead of "send to all active subscribers" from your send options. The segments are "rolling" so you can set up a segment now and as new people get tagged or have tags removed, the people who receive your emails will change based on the rules in initial your segment.

Hope that helps.

I think you understand it all. 

You would basically set up a rule that says when they buy this product add them to this list and apply this tag. Whether you choose to add them all to one list and use tags for everything, or if you choose to use different lists is up to you. 

The only thing to really think about is the fact that if you have confirmed opt in on, everyone goes to the same confirmation page, which is not always ideal. For that reason I create a list for customers and a list for the general list. But you can do it either way.

Good luck!