There are also spells that can improve your attack bonus, such as Bless/Aid and Magic Tattoo, and True Strike/Sure Strike (yes, True/Sure Strike are for the next attack only, but sometimes that massive boost to hit can make all the difference.)
In fact, I personally believe that one of the main reasons True and Sure Strike are Wizard/Sorc spells is to aid them with ranged touch attempts. Though they also happen to help alot when multiclassing (for gishes or arcane archers, for instance.)