Hey Robert. I'm a Sharepoint Developer and must say, I find it very interesting.
Most of the time Sharepiont Dev involves writing web parts or Solutions and sometimes Sharepoint Workflow (hope you dont have to do custom workflow as its a bit of a nightmare). Luckily , if you know ASP.NET , you're halfway there as Sharepoint Web parts are built using ASP.net. The most important thing though is to understand the Sharepoint Product. There are some good books/courses out there which will guide you in getting to know the product.
The Sharepoint object model (apart from the wf object model) is pretty good and provides just about everything you need.
I use alot of Ajax,Jquery in my web part, so also read up on that. Anyways, there's some good articles and references on this MSDN Blog. Hope my answer helps.
Good luck.
Oh, and by the way. DONT use VseWSS (Visual Studio Extensions for Sharepoint). It's cr*p (sorry MS). Rather use WSP Builder