I have made a concerted effort to get to 102.4%+ avoidance and 490+ def. However it appears that i have done that at the expense of my health. At 11600+ Health i am todl that its low. The question is where am i to pull this stam from without sacrificing avoid or def?
At this point in your gear progression, dropping briefly below uncrushable or uncrittable status is not going to halt your progress - do not under any circumstances pass up an upgrade just because it might temporarily threaten to drop you below 490 DEF or 102.4%. Upgrades are upgrades, regardless of those magic numbers.
Chances are when you do fall below, your next upgrade will push you back over the mark and you can keep forging ahead.
As for "where" to go: Karazhan and the badge vendor would like to have a word with you.