[TheLastSuperman]

So then do this:

• Install Cartplog.
• Redirect the subscriptions page to a category in cartplog housing the subscriptions you've added as products. *Only adding them so they're listed, you're going to change the template code next*.
• Change the button code so it subs out the cartplog product so you're actually signing up for a subscription, Paypal should handle the rest and then the subscriptions in vB will do the last part.

Basically you're using Cartplog but only as a container space for your different subscriptions, you're tricking the button in the template by modifying the code so when they click to buy the subscription the rest is handled by the vBulletin subscriptions system and paypal. Cartplog won't be used for purchasing at all per say but there to help you achieve what you want.

Edit: Ahh I may have overthought your initial inquiry... in PayPal there is an area where you can generate buttons and copy/paste the corresponding html code onto your website - that might be what you're looking to do here truth be told just read my above reply and you'll know which is the right way for you.