I also haven't bought any accessories.
After spending money on PSP accessories when I got one, I realized that I just didn't need them.
I cancelled my 4gig Memory stick Pre-Order and Pre-Ordered a 16gig instead since LittleBigPlanet Vita isn't releasing until June (according to the email I got from Amazon).
So now, my PSVita setup is looking like this:
PSVita 3G/Wi Fi
16GB Memory Card
Uncharted: Golden Abyss
I'm still debating on if I want to pick up Shinobido 2 from Amazon, and UMvC3 from my job. I should be able to get UMvC3 for about $20-$25 from the company store, I think. The discount is usually pretty good.
If I don't get those two, then I'll probably buy a few cheap PSP games off of PSN, for when I don't feel like playing Uncharted anymore. Speaking of, do any of you guys know/have heard, if Corpse Party will be compatible with the Vita? I'm buying it off of the PS Store in a few days, but wanted to make sure it worked on Vitas before I do.
I'm bummed I won't have LBP day one, but there's plenty of other cool stuff to play/do with my Vita.