Here are several names that often come up:

Break o Day
Green Gage
Bolseno Hybrid
Soux
Silvery Fir Tree

Lots of others mentioned here and there but You are correct, catalogs usually say sweet or balanced. My sister likes a really good strong taste too.

I like Green Zebra. Citrusy.

Azoychka - it's among the earlier yellows, and also has the citrusy tang. Not for people who like sweet tomatoes.

Carolyn has a list floating around somewhere, I think New Yorker and Wisconsin may be on it.

ddsack - Good to know about Azoychka, I am growing it for the fist time this year.