Goodness, that's a windfall! I can't really add anything here except to say that my rabble-in-arms are correct... don't blow it all at once! Spend some time researching, and spend some time on this forum, learning everything you can.

And as has been pointed out to me, you probably have shirts and shoes, boots perhaps, that will work with the kilt already. There's nothing like a t-shirt and boots wth a kilt. The most comfortable outfit you've ever worn.

Might I suggest one of these fine sporrans from the Scottish Tartan's Museum for casual/day wear. I love mine.