I'm using the standard Salesforce quote feature to generate quotes for opportunities.

My opportunity has a picklist on it which provides two billing address options (one being to use the original opportunity billing address, the other being a custom address).

As soon as the "New Quote" button is pressed, I am presented with the quote form, with the opportunity account billing address pre-populated in the "Address Information". Is there anywhere I can hook into this process to write up my logic to inject the required address (based on the picklist).

I'm fully capable with Apex/Triggers/Clicks etc. but just don't know what point I can take control of this button click? Is the Address Information configurable? Or am I going to be faced with producing a custom button for "New Quote" and all that entails..