+1 on Costco. You can find decent brands cheap.
I always recommend straight leg fit. It's timeless.
Tight is horrible fad. And Relaxed fit isn't much better unless you are fat. On normal people, it looks like a denim trash bag.
I'll sing the praises of Gap jeans forever. (sign up for their mailing list, they send out 20-30% off coupons all the time)
I hate Levi's, though, so feel free to discount my opinion... the idea that I need to "wear-in" my jeans for weeks before they become remotely comfortable bothers me. off the shelf, I find Levi's to be really stiff and uncomfortable. maybe they're magic after a few weeks of regular wear, but I've never managed to get past the discomfort stage to reach that point.
Real men wear Levi's.