First of all Hi Nedrip and welcome to the forums.

I have a 70 hunter and 70 priest, on different accounts, but I didn't try multiboxing them yet, so can't help much with that.

In terms of automating things a bit, quest acceptance, res acceptance etc, try automaton, mod available on curse gaming which is very customisable. Smart buff will probably also help.

In terms of levelling, things should get easier after 20. With only 2 chars, its still worth doing most collection quests, not as bad as 5 chars /gasp. Just follow one of the online guides like that at wowpro.com. Since the changes of 2.3 it should be easy enough, given the extra xp boosts. Just alternate collection quests between the chars and you should easily keep up with the guide.

For macros's I'm no expert, but:

http://www.wowwiki.com/Useful_macros/Priest
http://www.wowwiki.com/Useful_macros_for_hunters


are a handy start,

Good luck

Cheers Ky