Here are a couple of shops/stores I've had good experiences with:
Hostel Shoppe
Easy Racers Shop

As far as what accessories to get - I guess it depends on what your goals are. I added things like extra water bottle cages and a rack w/ pannier bags for longer distance rides and some planned overnight tours for next year. Also added a lot of safety stuff since i ride on the road with traffic a lot (front/rear lights, horn, mirror). The only accessory I'd like to add is a WERX or Zzipper fairing to improve the riding experience in a headwind.

Last, I don't think there is much you can do to really lighten a 31+ lb. bike up w/o spending a lot of money. At that point it would be better just buying something much lighter to start with. There are some nice lighter weight recumbents on eBay all the time.

Enjoy your ride!