I've just unlocked ebony armor and recovered the Forgemaster's Fingers. I have to turn them in to get friendly with Orcs and access the Ebony mine. It's that, or kill everyone, which is well within my power. Any advice? I'm an elf, so part of me thinks I should just kill them all, but I don't want to close any doors that I'll need in the future. I also like the bonuses for smithing. Any advice?

Do a quest for an orc who lives outside of the strongholds. Once they name you 'friend' you can enter any stronghold

Markarth is a good choice, since it has three orcs with quests - there's also one at Karthwasten

The librarian at the College.

Or visit the stronghold of the 'cursed tribe'.

That's what I usually do. I love doing that quest, I kinda like malacath.

Turn in the fingers. You will find other items in the future that are enchanted for smithing, which you can disenchant in order to learn the enchanting spell, and then enchant your own gear. Smithing can be applied to gloves/gauntlets, armor, rings and necklaces.