You might want to e-mail me on firstname.lastname@example.org
and that way I can send you copies of anything I can find (if you want me to look for you, which I am happy to do). If you just want me to suggest some ideas we could stay on this message board.
I expect you have looked at the Familysearch website - I had a quick look and there were a few merchant navy records, 1 born Armagh, 1 Co Mayo and I 1823 (probably too early) but not much info. Also: www.emeraldancestors.com
is a good website but you can only see so much info before paying (£10pm - not bad) I couldn't find anything for austin but there was a death for Jonathan Smyth in 1860 in Armagh. http://www.rootsweb.ancestry.com/~nirwgw/armagh_nirgw.html
has a big list of Armagh websites that might be useful. Griffiths Valuation records show who rented and owned land in Ireland so you should check that out at: www.ifhf.rootsireland.ie
and you will also find BMDs etc there. You probably realise that Smith, especially in Ireland, is very difficult - I have been looking for some Smiths in Co Tyrone for about 3 years and not got very far, but you never know what you might find so worth a look. Hope this is some help. Get in touch by e-mail if you wish. Chris