Barry,
The only butterwort I grow is Pingucula Bhoemica

^ this picture isn't mine, just a stock photo I found on google, mine is still pretty tiny.
I've only been into carnivorous plants for a couple years, but in my experience all of the carnivores ranging from Australia through Thailand do really well in some combination of sphagnum, pumice, and canadian peat. I keep a bog box that I started as a full bed of sphagnum then once it got rolling I buried my carnivorous pots among the moss and keep a dome on it under lights to contain the humidity. It works really well for every variety I grow so far. Check out a book called The Savage Garden. It covers just about every attainable carnivorous plant.

Also on this topic of random books and fungal gnats, a book called Carrots Love Tomatoes has all sorts of nifty tidbits on using plants to repel certain pests, and just other random helpful hints on companion planting.
