I guess it depends on what you call a "neologism"

I don't consider "komputilo" to be a neologism at all; it is not a neologism, in my mind, any more than "hundego" or "kanteto". It is the combination of a long-accepted Esperanto root ("komputi") with the standard Esperanto suffix -il-, indicating "a computing tool" (i.e. a computer). Perhaps you are thinking about "komputero" or "komputoro" (both official, I believe! and meaning the exact same thing as "komputilo")

The Academy does "officialize" words but only after they are in long use. You won't find them in a separate dictionary (that I am aware of - aside from the Academy's website, which does have a list) but most good Esperanto dictionaries will mark them somehow. I believe even the PIV will mark out these words.

I personally separate Esperanto dictionary words into three categories - Zamenhof's words (often marked with a Z in a good dictionary), official words (either from the first Esperanto glossary or from one of the Academy's official additions to the dictionary - these might be marked in bold, or by "OA" [oficiala aldono] and a number, or perhaps an F for fundamento), and the rest of the words. So if you are extremely concerned about "correct speech", you could stick to using only the words from Zamenhof, the Fundamento, and the Oficialaj Aldonoj. I believe the Academy has a full list of them on their website. This may be the "standard dictionary" you are looking for. However, the members of the Academy have day jobs, and I think you will find it is not always easy to speak sticking only to words that have been made official. But it can be done.

If you look at www.reta-vortaro.de they have different word categories clearly indicated in the lists.

In any case, as you can see - we have official and unofficial words, and you can see how much people care (or don't care). But I think most Esperanto speakers are not interested in adding zillions of new neologisms and I don't foresee any splitting into dialects. I think it would have happened by now if it was going to happen, especially in the early days when communication with distant Esperanto speakers was difficult and more limited.

Claude Piron in his essay Evolution is proof of life has explained why komputilo is a neologism and how it became part of E-o. I would regard this as a word that made the transition from being a neologism to being part of the language. To quote Piron:

"When computers appeared, they were first designated by such expressions as elektrona kalkulilo 'electronic calculator' or informtraktilo 'a device to treat information', but the words komputoro and komputero were soon in use besides them. However, the suffix -ilo is so common for that kind of concept that the average Esperanto speaker quite naturally substituted komputilo for those words which were competing between themselves, neither appearing more likely to win. In fact the word komputilo already existed, at least in dictionaries, with the meaning '(gas, water) meter'. Today, the language obviously hesitates about the word to use for rendering the latter. Some say adiciilo, others sumilo or nombrilo, somebody proposed sumadilo (-ad- is a morpheme emphasizing duration or repetition: sumadilo means 'a device that is constantly calculating the sum'). But there is no doubt that komputilo has already definitely replaced both komputoro and komputero. As a consequence, due to the language structure, the verb komputi now suggests the utilization of a computer."

But Piron also talks about how the community of users, rather than any authority, brings about evolution:

"It is interesting that very often authority decisions are not taken seriously. For instance, the neologisms komputero ‘computer’ and dateno ‘data’ were officially agreed upon and recommended by the Computer Section of ISAE, the International Association of Esperanto-Speaking Scientists. But they did not last long. Today most computer specialists – even the above-mentioned section of ISAE – use komputilo and the older form datumo.

Most arbitrary decisions of that kind had the same fate. Although the principal explanatory Esperanto dictionary, Plena Ilustrita Vortaro, enjoys a considerable prestige, a good many forms it recommends have never really been accepted. While it recommends televizio for example, everybody says televido. It appears that the speakers of Esperanto have developed a sense of what can and what cannot be assimilated into the language. They have a subtle feeling of how it should evolve, even if they would be at a loss to define it."

This 'sense' will hopefully counter the tendency to invent neologisms ad lib in a way that would detract from the international accessibility of E-o. William Auld's call for a dictionary of 'good' E-o still remains valid, in my view, if we use 'good' to include adequately respecting this 'sense' of the user community.