So based on my experiences and opinions so far, this is what I have to say about NTWFSFE syndrome. [NothingToWearForSemiFormalEvents syndrome. Long syndrome name, but hey, I made it up just now so how am I supposed to think of some cool medical name for it?!)
1. According to my school orchestra teacher (yes, orchestra teacher…) a No Jeans event is also called business casual. A simple way to wear “business” casual is black dress pants and a pretty top. My suggestion for a "semi-formal" top is something with no logos, no pictures, don't bare a lot of skin, and either solid colors or a bold print. Black shoes always go with black pants. Be simple. Just do me a favor and not wear white socks. Please. [If you happen to be totally against black dress pants, my tip is to go for black yoga pants that fit. I know somebody who borrowed yoga pants for a formal event from someone else, nobody noticed they weren't dress pants, and she still hasn't given them back to the original owner! *COUGH COUGH SHE WANTS HER PANTS BACK*:)]
Dress Pants: Macy's. Yoga Pants: Old Navy.
2. Of course, dresses always work. If you want to blend in, wear dresses that are around knee length. Toss on a cute sweater. BAM. Perfect semi-formal event outfit. However, I know that alot of people are afraid of their looks being too formal, or too casual. Add leggings, tights, layer with tanktops or camis underneath, add a short or long sweater on the outside. There. You're neither formal, nor casual. Perfection.
Still have NO IDEA? First off, a good looking simple black dress can be found anywhere. Even Target! Try layering with sparkly tanktops underneath the dress (I found my gold sparkly tanktop at Express), if you want to make it more casual-ish, add leggings or tights (American Apparel, Macy's, Urban Outfitteres, etc.etc.), and instead of a jacket, add a cropped sweater or shrug.
Simple semi-formal example: