Years later, in an online Q&A, Gary gave a bit more info: "Bucknard was an NPC I created out of whole cloth. He was based on a neighbor of mine when I was a lad, a Mr. Bucknall. He had a great garden, an apple tree with five different kinds of apples, and he knew astronomy well, assisted me with my 100 power telescope. He did use a small change purse, and from it he would extract a small coin to give to me now and again;" while Otiluke was a portmanteau of the names of his son Luke and Luke's character Otis. We know from Temple of Elemental Evil that Otis was a ranger, not a wizard (and that he was also a PC, not an NPC), so it seems likely that Otiluke was intended to be a different character than Otis, but perhaps sharing some of the same personality traits or other characteristics.
Armed with that info, and knowing that anything more is not likely to be forthcoming, I decided to go ahead and create my own versions of these two characters for my personal World of Greyhawk. Therefore, we now have:
19th level Magic-User // 6th level Druid
S 8 I 18 W 19 D 11 C 9 Ch 14
Bucknard is an older, now-retired wizard who also has abilities as a Sage (Major Field: Physical Universe [special categories - Astronomy, Geology, Meteorology]; Minor Fields: Flora, Humankind). He formerly maintained a curio shop in the Foreign Quarter of Greyhawk's Old City but now resides in a secluded estate in the Garden Quarter. On his estate is a tree that grows five different types of magical apples with minor beneficial effects if consumed immediately, but only once ever per character per apple-type (bless for 4 hours, cure light wounds, +1 Joss factor if used within the next 24 hours, +1 on saving throws vs. poison for the next 24 hours, heightened perception: +1 to spot traps and secret doors and avoid surprise for the next 4 hours). He has a kindly disposition and if sought out (since he does not advertise) may be willing to provide information and services (identifying items, etc.) to good-aligned adventurers, though he typically requires services (retrieving rare components, etc.) in lieu of cash payment and he always works on his own schedule and cannot be rushed. Bucknard is on friendly terms with both Celestian and Zagyg (an association that possibly stretches back to the latter's mortal days) and is rumored to have been an early mentor to Mordenkainen. The Striped Mage and the Sages' Guild of Greyhawk both resent him and would like to see him disappear, but have so far been unwilling to take action against him thanks to his powerful allies.
Note: my friend Gene Weigel, who tracked down Gary's quote above about the Bucknard/Bucknall connection, and also discovered that "the Bucknall Brothers" ran a dry goods store that was still standing in downtown Lake Geneva in the 70s, located right across the street from TSR's offices, also created his own tribute magic item that can be used in conjunction with (or in place of) the above - the apples in Gene's item could replace mine (or vice versa), and/or the tree on Bucknard's estate might be the only place where the magical basket can be refilled.
16th level Magic-User
S 12 I 18 W 9 D 17 C 16 Ch 15
Otiluke is a prodigy-wizard, younger than the other archmages but just as accomplished. He's very energetic and enthusiastic but also perhaps a bit naive. The other wizards tend to treat him condescendingly, which he resents, so he's always trying to prove himself to them, which sometimes leads to rash or risky action. He is more friendly and solicitous towards low-level adventurers than the other, more aloof, archmages, and enjoys serving as a mentor and having his advice sought. However, his exuberance occasionally causes him to unintentionally direct lower-level parties into situations too dangerous for them to handle! His closest known associate is Melf of the Green Arrow, and he bears a particular enmity against Wastri, the Hopping Prophet.