I usually buy my batteries at Sam's club (costco) for my cars and motorcycle. They are either duracell or energizer car batteries. Have the 2nd battery in 10 years of owning the fiero and I am in a fairly cold area as well
I've bought my last few AC Delco batteries (for several Fieros) from private tow truck drivers who "salvage" them from cars they're hired to drag to the wreckers. I always check the date of manufacture before purchasing, and I've got some great deals.
I cant believe know one mentioned Optima until now. I started using optima because they are sealed gel which means they do NOT leak acid. I used a deep cycle marine blue top in a trans am I restored. The battery drained stone cold DEAD at least a half dozen times during its life and I still got 12 years out of it. I am gonna replace it this season, its still in car and starts but its just getting tired at this point. Since that first purchase I bought 3 more for other vehicles including one for my fiero. They are expensive but I think cost per start, in the long run they might be cheaper as they last a very long time. I live in NE PA and in the past most regular batteries would last me abou 4 years on average. By the way I think Amazon has the best prices on Optimas.
I can get a little more than a year from a Walmart battery in the Fiero and I gave them 3 chances. I'm trying a Sears Diehard now.
------------------ "Kilgore Trout once wrote a short story which was a dialogue between two pieces of yeast. They were discussing the possible purposes of life as they ate sugar and suffocated in their own excrement. Because of their limited intelligence, they never came close to guessing that they were making champagne." - Kurt Vonnegut