Proper Ice looks more like rock salt or smallish chunks of crushed ice - hence the name.It is only in powder form if your dealer has jumped on it ie he has crushed it to make it look a bigger size and/or adulterated it.Oh and make sure it actually isnt rock salt, ice and other amphetamines have a very distinctive bitter taste, once you have tasted it you'll never forget the taste.
As to the effects, they are similar to the other stimulants except that ,ice is a much higher quality upper.
Expect to have feelings of euphoria,talkativeness,lucidity,unbounded energy,insightfullness, and a general feeling of well being.
As to the after effects ,well it depends how much you have and what you do.The comedown is quite mild compared to other uppers and very tolerable.You will feel fatigued , mainly from what you've done rather than the drug itself.Your vision may get a little blurry mine does anyway (could be because I'm getting too fucking old, haha!!).Make sure you drink plenty of fluids I find this helps me.
You can either smoke it, blast it, ingest it ,or snort it.
If you smoke it use a glass pipe or off a light bulb (do a search we've discussed it to death - thanks PhreeX).
Have fun on your journey ( you will probably walk heaps )!!