I'm sorry I can't attribute this recipe but this is the combination that has worked best for me and gotten me closest to restaurant taste, though not texture:

Ingredients:
* 3/4 oz. dried wakame seaweed
* 3 tbsp. rice wine vinegar
* 1 tbsp.sesame oil
* 1 tbsp.soy sauce
* 1 tsp. sugar
* 1 tsp. ground white sesame seeds
* Hot chili flakes
Preparation:
#1
Soak the wakame seaweed in a bowl of warm water for five to seven minutes. Drain water and pat seaweed dry with paper towels. If needed, cut wakame into thin noodle-like strips. Put seaweed in refrigerator.
# 2
Combine vinegar, soy sauce and sugar In a bowl. Whisk together until sugar is dissolved.
# 3
Slowly add the sesame oil and whisk dressing together.
# 4
Add seaweed and toss with dressing. Add the sesame seeds and chili flakes to taste. Serve seaweed salad immediately.

I've wondered the same thing! Thanks for posting.

@Teawithpaloma - do you need to soak the seaweed first in water?

@pbelardo - Click on "show more" in teawithpaloma's comment. There are full instructions, including for soaking. :)

I think it's all in the dressing. Your basics should be rice vinegar (or plum?), toasted sesame oil, soy sauce (or tamari or fish sauce), honey, and freshly grated ginger--all to taste.

I started adding roasted sesami nori strips to my Asian-inspired salad. I break each small strip into little pieces.

I think that the type served in most sushi places comes pre-made (dressing and all) and frozen. From what I've been able to dig up, the "seaweed" is actually an extruded stuff containing agar-agar (which is from seaweed). So my attempts to make it from real seaweed all failed.

I ended up buying a 5lb box of it from my local Asian market for about $30. It can be had on the internet as well, but is expensive because it ships frozen. However, if you want the stuff from sushi restaurants, this is what you need to buy.