My players are playing a warlock, a ranger, a rogue/fighter, and an adept (tier 4 campaign). The adept is a knowledge-based adept, and is trying to research a way to stop an ancient evil. Three of the four characters can be doing other things (gathering material components needed for the ritual, etc.). So, the question becomes, how do I make the session interesting for everyone? The obvious option is to have NPCs do the research, but that invalidates the character who is putting forth effort to know how to do research himself. But, if I have everyone else sit around while the one character is researching, that will not be fun for anyone else.
Are there any sources that describe how to handle research to make it enjoyable for everyone? Does the researcher take the heavy book with him, and as the party is fighting, he is rolling into initiative to battle tough passages? That seems contrived. I have seen the research feat in the Eberron Campaign Setting, but the character has not taken the feat yet. So, without it, the character is looking at weeks of downtime to gain the knowledge he seeks? He gets a feat next level (he is a few hundred experience away). Would it make sense to give him the feat a bit early, just so that research can go faster and not distract from the rest of the game?
Any articles or sources that might help me figure out how to make this fun would be extremely appreciated.