I agree with what Lee said and would add that you could;
1. post a question over on the Rum Soaked Fist
Request a Teacher forum and you'll probably get some recommendations.
2. My experience is most of the gym and community center teachers are doing the flowy/qigong/health by moving type of Tai Chi and lack the real meat and potatoes of IP/IS.
#1 is almost guaranteed to produce #2.
And if you find the good ones?
Experience keeps demonstrating that their students didn't get it-and are never-the-less convinced that they did!
I love...LOVE a quote given to me by a ICMA Chinese grandmaster taiji teacher.
"There are...only...CHINESE grandmasters."
Implying that there will ONLY be Chinese grandmasters.
It's not a a very comfortable thing to hear, but for a short sentence, it say quite a lot!