I use Weleda's Babycreme
You can get it in DM, Müller, probably in any pharmacy, or just off of amazon. I have to say, though, that I don't know how well it works for real rashes. Thankfully DD has never been prone to them. I just use the Weleda cream when her butt's getting a big red (happens if she poops several times in one day, which is a fairly frequent occurrence).
Usually I like Hipp's stuff, too, but I've never tried their diaper rash cream before. For a zinc oxide cream, we still have something from the US that my parents brought over.