I bought the victorio 4-tier sprouter from William and Sonoma. Here's a link:
sprouter
Believe it or not it was the cheapest I could find that one for ($10). It's small (only 6" diameter). But I bought 2 (4tiers each)so I have one everyday for them and just rotate. I haven't had any trouble with molding. I know people sprout in canning glass jars but I think the lend themselves more to the mold problem. I put my sprouts all out at night so they breathe more. Then I stack them during the day switching which ones on top. It's been easy and quite fun to see them growing. I've tried chia, barley, alfalfa, wheat. I'm going to try some beans too because I have some old ones that weren't stored well. It's been great so far with no mold at all.