It's on the north side of New Albany, no more than two hundred yards across Grant Line Road from NABC/Rich O's/Sportstime (same side as K-Mart, adjacent to the liquor store).
http://cityofnewalbany.blogspot.com/2007/09/another-la-rosita-taqueria-planned-for.html
I'm not sure about the hours, but it's been packed for lunch. Israel's not doing the full menu, just the basics (tacos, quesadillas, burritos) like he did at the old, now defunct Charlestown Rd. location. The Market Street sit-down Rosita's also was packed the last time we dropped in, so I believe things are going well for the Landins.