I've met a fairly new Mage Wars Arena player over Facebook who wants to compete in a local event near him, but he is very new to the game. He's at Gen Con this year and he thinks he's probably not going to participate, but he would like to get some practice games in regardless. What are the best competitive spellbooks that are easiest for a beginner to learn how to use? Any suggestions?
I'd say let him start with the default books that AW suggest and let him play, play, play. It does not matter at all when you lose in the beginning.
Only during play you will notice what others do against which you cannot do anything or visa versa. So you'll learn to balance your spellbooks.
There is also the question what a competitive spellbook is.
a) OFFENSIVE: Something wild that 50% of the all-round mages cannot easily counter, but the other 50% can.
b) DEFENSIVE: A more balanced all-round spellbook, that lacks surprise, but will lead to longer games.
I learnt GW by playing the default spellbooks and then adjust them over time.
Also watching games on youtube can help to spot interesting combinations of cards, around which you can build a book.
Spellbook building is half of the game. But you need to understand the dynamics of the game to properly get into the phase of spellbook building. The default spellbooks are fine for that purpose.