I find that getting upgrades from AH when you are having trouble are a huge help. Best way is to filter for rares of your level and then descending buyout price. You will have to scroll a few pages to get out of the N/A's, but once you do you find really low priced items! Hard to find any other way as there are millions of people selling items on this AH and it will only show you what you ask for otherwise you will only see a random 48 page item list.
If I remember correctly, the best thing to do is dodge the green circles on the ground. Other than that, DPS him down as fast as you can. I died the first time around on my barb until I learned to avoid the circles.