Hi Deb, I haven't heard of Michael Stars tees, but there are several t-shirt manufacturers that specialize in "fashion forward" type t-shirts:
AmericanApparel.net
Article1.net
Continental-USA.com
Bella.com
ASTees.com
Kavio.com
AlternativeApparel.com
theapparelagents.com
You may want to look through the above websites and catalogs to see if any fit your needs.
Most likely, the t-shirts that Michael Stars sells are custom made to his specification. This is done in MASS quantity (like 100's and 1000's per design).
So it can be a challenge to match the exact style of big name brand shirts you see in stores. They have bigger budgets, so they can do fancy things
If you're at that level, then you can contact manufacturers directly and have them custom make a garment for you. But if you're not ready to order 100's or 1000's of t-shirts, then it probably makes more sense to just find one a design that's available wholesale from one of the above vendors (or other vendors that I may have missed

)