I actually find
most running sneakers tend to be vegan. Leather is just way too heavy compared to synthetic.
Personally I run in a couple of different shoes:
Vibram Five Finger KSOs - love the minimalist, barefoot-esque feeling of these. Will run more in them after my upcoming marathon & after my foot injury (see below) heals up some.
Saucony ProGrid Kinvara - recently picked these up on sale ($60) from roadrunnersports dot com; very lightweight with a wide toe box so they are pretty comfortable. Low heel rise so they tend to make you run more with a midfoot stride.
Adidas adiZero Mana - also lightweight (about the same weight as the sauconys) - narrower and a little more heel rise (so less front/mid-foot stride)
I like to mix them up. I would be running in the VFFs all the time but I had a foot injury this summer that hasn't fully healed yet and I need some padding.
I used to run in Nikes, but they are pretty heavy compared to these shoes and, for comparison's sake, tended to make me feel like I was running in mud.