Shrimp ceviche is pretty easy, it just takes a lot of chopping. But it's definitely worth it, if you want something light, fresh, and delicious.
Start with the shrimp - this time, I used a 1lb frozen bag (they were on a 2/1 sale, what can I say?), so defrosted them, brought a pot of water to a boil, and cooked them until just done. Drain, then dump into an ice bath. When cool, chop into little pieces (maybe 6 per shrimp), and refrigerate.
For everything else: Dice 2 tomatoes (I got rid of the seeds), slice up 1-2 green onions, dice about 1/3 of a red onion, and chop up a handful of cilantro. You could also mince a jalapeno or two, but I forgot to buy them.
Throw all the veggies in a bowl, and squeeze in the juice of 2 limes. Add the shrimp, and mix. Dice an avocado, and carefully fold it into the shrimp/veggie mix. Chill for a bit. Serve with chips.