I run a 39t chainring and an 11-34t cassette on my Surly Pacer. I have an old triple front crank with the small ring removed and the big ring replaced with a salsa crossing guard. I don't think you would actually need the crossing guard (to keep the chain from jumping), but it was an easy way for me to re-use my old chain ring bolts.

I love 1x9 soo much. I wish I had gone to it a long time ago.