For imbuing...
Train imbuing on a smith (I stoned mine over, when I relise how much easier it would be). They can make daggers for 3 ingots, exceptional all the time if you're high enough.
You'll want exceptional items to imbue, because that will mean you can use the lower intensity imbues to train, for way fewer gems. At 65, I'm still only using 1 gem per attempt.
Hit Dispel uses Amber, which is the cheapest.
I use 3 UOA macros:
1.) to imbue my current property onto a dagger.
2.) to unravel a dagger
(for both of those, for some reason, they pick from the top of the same list, so it'll attempt to imbue the same one as it attempts to unravel)
3.) make 1 dagger, imbue to dagger, unravel dagger
(unravelling the dagger after one imbue ensures you pretty much break even on residue, at 50/50 success/fail)
Gains have come pretty fast since getting that all sorted.
Of course, massive advantage for lining Tug's pockets *mutters*
Not even SA is close to as effective.
On cost, it's actually not really that much off smithing, or tailoring using leather (not that you have to use leather any more for tailoring, with gargish cloth armour).
3 ingots (60gold@20ea), 1 amber (say, 80gold). So it's about 140gold per skill check, which is pretty steep, but only about 7 ingots in cost. And you can mine gems these days.
