Don't waste yout time and money on App2 spells. They are not that much more powerful.
Spells come in 3 flavors:
Apprentice (easy to craft)
Adept (mob drop [1] or crafted with rare components [3])
Master (mob, quest, or level reward)
Components bought at the vendors can be used to craft spells but they are lower quality and will "cap" the spell at a lower level.
You can easily craft your spells to App 3 or 4 by either foraging for the components or buying them from the broker. Remember that when you craft, the primary component (listed at the top of the recipe) must be PRISTINE quality to get an App4 spell.
Check out a great crafting and recipe site
here.
If crafting is not your bag then you can save up some cash and buy player-made spells from the broker. Depending on the market, expect to pay ~40s for App3 and ~95s for App4. Expect to pay a gold or 2 for Adept spells.
I raised a Gnome Priest up to level 9 Artisanr while on the Isle of Refuge and crafted Smite to App3. He is now a 14 scholar and has crafted most of his Druid spells up to App3 or App4.
My 30 Conjurer still has some App1 spells (Invisibility for one) that function just fine, although someday I'll look to upgrade them. All her damage and pet spells are App3 or higher.