Thanks for all your advice. Any tips for finding steel mats?
Do you mean the materials needed to make steel?
In all honesty it comes down to your embark location. If you cannot find iron by digging, then you need to get iron in other ways; trade, transmutation via the alchemist, processing ironbark logs at the herbalist, and the trading workshops. You can also produce iron and steel via the shrine of Armok by praying for hard metals.
Getting flux usually just means digging until you hit flux stone. Generally I find that most embark sites under the mod's usual map generation formulas have a layer of flux stone, but it may be very deep and does not always show up on the embark site information when choosing a location. You can also grind bones into bonemeal (which is a flux) at a millstone. Boulder Crabs also lay flux stone eggs and can be butchered for a flux material. Finally, you can still get it through trade.
My preferred method is just growing the stuff with ironbark and steeloak trees and getting the bars out with a herbalist. I find that shrubs of ironbark/steeloak is present on plenty of biomes so if you are lucky you may be able to harvest some with the gather plants designation, otherwise you can probably trade with humans, dwarves or elves for the seeds (I do not know if gnomes carry 'em). My second preferred method is through having a cleric constantly pray for hard metals.
