Good luck at a retailer. What you need to do is put your name on the Auto-Notify list on Newegg.com. that is what I had to do with my 5870. I also kept the search for 5870 on my screen all day and hit refresh. They go fast and you have to catch it. I was hoping for an XFX, but the ASUS cards were delivered yesterday at Newegg so that is what I got. If you are stuck on XFX you are going to wait a while or be very lucky. Honestly they are ALL the same right now with the OEM cooler. Until companies start to make their own coolers for these cards, there really is no difference besides the support the company provides. XFX has the double lifetime warranty, which is the BEST. But I've never had an issue with ASUS and they have a 3 year warranty, I don't intend on having this card 3 years so I am good.
Good luck, the 5850 is in shorter supply than the 5870's. They has the ASUS on newegg yesterday, and I saw the XFX pop up just an hour ago on Newegg, but if you add it to your cart they were already gone.