I don't like my upper arms.
I got some basic tees at banana republic this season that are elbow length.
I just got a blouse (long sleeve light weight material) at target and I'm wearing it with the sleeves rolled. I got a 3/4 sleeve top at target too. Both are thin dressy material (but are prob polyester).
I also got a tshirt at Talbots with elbow sleeves.
If you are in a/c I recommend layering with a blazer or topper and them you're good to go.
There is a thread (search for it) about inverted triangles (IT) and longer sleeve lengths - lots of links and suggestions on that thread.
Good luck.