Steelhead are without question my favored fish. I can close my eyes hit play and re-live my first fly caught steelhead on the Yuba river in California on a large skated caddis.....
First to speak to patterns sounds like you have a pretty good arsenal already. I would suggest sticking with a half dozen patterns and vary sizes and silhouettes. I like sparse patterns with motion, green butts skunks with seal dubbed bodies or floss bodies, night dancers, purple perils I dress similarly. Something bright something dark and in between size #1-#6, Don't forget your muddlers either.
Rods, depending on where you are fishing. Single handers I like the 7100 Sage. Aslo fished with a long belly or DT for roll casting. But I have converted to the two handers even if I haven't figured out how to cast one yet.
Books, the books Juro mentioned are great and without question a solid place to start.
Yes, you can become obsessed with a fish you've never caught! Let me know if you are thinking of the Deschutes I'll try to get you out. What are the dates again? Juro fall steelhead 'clave Cow, Deschutes???