A "sorcerer" kit appeared in Arabian Adventures (1992).
The sorcerer as a spontaneous arcane caster was an original invention of D&D 3rd edition. Prior to this, sorcerer was just a synonym for "wizard". However, there were several kits or classes in AD&D known by the name "sorcerer".
Classes named "sorcerer"
Original D&D (1974) used the name "sorcerer" as a level title for any 9th-level magic user.
The Al Qadim sourcebook Arabian Adventures (1992) has a sorcerer kit, a kind of specialist in two elements (p.40):
Sorcerers are the standard and most common wizards in Zakhara. They can draw from a pool of universal spells, and they have specialties as well. The "official" mage of the AD&D game specializes by school (alteration, divination, and so forth). In contrast, the sorcerer specializes in two of the four elemental provinces—wind, sand, sea and flame—in any combination.
The video game tie-in sourcebook Diablo II: The Awakening (2000), one of the last sourcebooks released for AD&D 2e, added a sorcerer kit. They are a specialist in Conjuration/Summoning.
The Complete Wizard's Handbook (1990) had an Amazon Sorceress kit.
The Planewalker's Handbook (1996) had a Floating Sorcerer kit, an air specialist.
The Dragon Magazine index shows no kits named sorcerer in that magazine, and all articles it lists on the sorcerer are for D&D 3e. This suggests that Dragon never published a "sorcerer".
Note that most D&D sources prior to 3e use the term "sorcerer" and "sorceress" as simply aliases for "mage" or "wizard" without referring to any specific class or subclass. For example, even as late as 1996 with Player's Option: Spells & Magic, an invoker and a mage (both existing specializations of wizard) are each referred to as a "sorceress".
Spontaneous arcane casters in general are almost as old as D&D (1974).
According to Playing at the World, non-Vancian spellcasting was one of the earliest house rules applied by D&D players, who felt it unreasonable that the first-level wizard only cast to cast one spell per day. In fact, many groups allowed it by accidental misinterpretation of the rules. This was one of the first forms of spontaneous casting in D&D.
Since unlimited spells per day made higher-level spellcasters too powerful, many groups instituted a spell points system. An official version of the spell points rules appeared in Player's Option: Spells & Magic (1996).
However, it wasn't until D&D 3e that "sorcerer" and "spontaneous arcane caster" became synonymous. The spontaneous caster was an invention of D&D 3.0 (2000), as was the suggestion to associate "sorcerer" with this meaning. This is supported by an early interview with Skip Williams:
Q: When the D&D team looked at building a new spellcaster class, what gaps in the game were you trying to fill? Were there specific things you knew you wanted this class to bring to the game?
A: Mostly, we were considering the age-old complaint about wizards having to "memorize" spells each day (in the new game spells aren't memorized, they're prepared).
We considered a system of spell points, but those don't work terribly well, so we resurrected a concept I first played around with when I was in high school: a magic-using type with a very small repertoire of spells that could be used freely.
Q: Was there much discussion about the name of this new class, or was sorcerer at the top of everyone's list from the start?
A: Somebody threw out the name "sorcerer" and it just stuck.