Yep you're an addict!
Much good advice already in this thread. For what its worth, here is my $.02.
Books -- Trey's big book is the bible. Depending on where you plan to fish and what time of year, others are good reads as well. A few I have enjoyed are Steelhead Water and Steelhead and a Floating Line. Both are by Bob Arnold. Juro is right about Helvie's book of patterns!
Rods -- I'm also a double-handed convert and rarely cast my single hand for steelhead but I am partial to a 10' 8 weight but then most of my fishing is winter/spring with tips. For summer runs, a nice 7 weight is hard to beat. I prefer longer rods as they mend so nicely. A couple of good rods are the Scott ARC and STS (no longer made in the 10-08) and I also like the Sage SP in 9'6" and 8 weight.
Flies depend on your preference more than the fishes. Also dependant on when and where you are fishing. A spring day on the Skagit or Sauk calls for a different dressing than September on the Deschutes, Grande Ronde or Snake. Find something you like and tie it in a couple of sizes and colors. If I could fish one color it would be purple but a lot of others would argue for black. As an old time Skagit hand told me one time, "I fish any color as long as it's black". My third color of choice is burnt orange.