HA! Finally something I can add useful advice to. My girlfriend plays high elves, so i've got more experience with them than any other race. I guess a bulleted list with a few useful points are in order.
-Arsenal is completely correct, salamanders do wonders on high elves, specially larger blocks, pretty much any infantry besides phoenix guard.
-Tiranoc Chariots dont do alot of damage in hth but watch out for lion chariots, they sting. A potential of 12 str 5 hits and fear kinda sucks.
-Skink skirmishers are a great way to take out obnoxious stuff like swordmasters (other than salamanders) that would devistate you with ASF in hand to hand. Their armor save isn't great, and they're only toughness 3, so even the nonpoisoned shots can do damage easily.
-Watch out for White Lion infantry. They wound on 2's with saurus and are stubborn. Not a good combination.
-I've found that cold one cavalry used in minimum sized groups works great against spearman/seaguard blocks, even if they strike first. I've whethered through 18 attacks with ease to strike back and kill off 6-7 models with 5 cold one cav. If they fail thier fear test and need sixs to hit, all the better!
-Dragons tend to be a problem, as they are really fast and can eat a stegadon on the charge. Blowgun it lots!
-Use skink cohorts to helpfully redirect big scary dragon princes for a flank charge. Keep DPs from charging something important at all costs!
-Terradons are great at bolt thrower killing
Hope that helps a bit!