Does the Italian mean that one actually found enjoyment in reading? In English to say "I found little enjoyment..." means you found "no enjoyment", if you want to say you enjoyed it, you say "a little enjoyment", or "some enjoyment".
It's a substantivation of the verb, same as "reading" in the translation; other languages make it more explicit, for instance it would be capitalized in German (Lesen), being used as noun (all nouns are capitalized in German).
Is the voice pronouncing this oddly or does the emphasis actually shift from LEG-ge-re to leg-GER-e in this context? It sounds like the pronunciation of "legero" except with an "e" stuck on the end...confusing.
No. The sentence means "I have found little entertainment in reading" as in "next to no entertainment" or "almost no entertainment". That's why it shouldn't have the article "un". It's not "a little entertainment".