Ok, I've found about a billion lists of what spells will make your wizard a gawd and how to pick the most effective spells for a cleric, but as a DM, I'm really interested in how to get the most mileage from my adepts.
Assume that the adept in question is supporting a group of five warriors of the same level that he is. What are the best spells to select at each level? What are some tips and tricks that can make this fella shine?
Cure spells + invisibility is a great combo. As long as you don't directly attack the players, the invisibility stays up. You can heal your friends to your hearts content. The same goes for buff and some control spells. Bless, obscuring mist, darkness, bull's strength can all be cast without dropping invisibility.
If you are going to be more offensive, don't neglect your defensive spells. Mirror image and resist energy should keep the players from one rounding the adept when they appear. From there focus on control spells that hinder the players even if they make their saves or don't allow a save. Web and deeper darkness are both good spells for this.