The schems are cheap cheap on the GTN, don't learn Slicing if you only want the schematics.
But since you do need slicing materials to make the augments it is worth it.
that being said, you HAVE to crit to have a chance at getting a schematic, and even then you are pulling from a pool that includes armormech and armstech schematics as well.
It boils down to two options:
if you have the patience, create a slicer or two and hope you get the schematics you want/need. In the meantime you will also get materials you need to make the augments after you get the schematics.
if you want the schematics now, buy them off the GTN. However, that also means you will have to buy the sliced materials off the GTN as well.