:welcome: This is an exciting (And Scary!) time for you. :2thumbs:
Basically; there are (or will be) four models:
RT: Designed with two-up touring in mind. Has the most luggage capacity.
ST: The model that has "Sport-Touring" in mind... It'll haul you cross-country, but has more of a Sporty DNA...
RS: This is the bike that started it all... It's the Sporty one; built to turn heads, and handle the twisties
F3: The new kid on the Block. A bit of a bare-knuckled brawler, with a cruiser-style seating position.
Within the models, you'll find the sub-models... :yikes:
They are used to differentiate between the various levels of "Goodies", that the bikes come with.
Here's the link to BRP's website; but don't hesitate to ask questions in here! :2thumbs:
http://can-am.brp.com/spyder/