That's not what i'm asking. I have the resources, i'm just a bit overwhelmed, so i'm asking how to research efficiently (e.g. what to research first in a complex, how to not get overwhelmed etc.). In essence, how to use them efficiently.
There's no easy answer here. You have to start with a concept, which is from your imagination and not from research. The concept will provide the limits. If you were to give us an example of a concept you're trying to research, we might be able to give you some guidance as to how not to get too overwhelmed.
I start with a concept, in my case, an or a set of contiguous, related ecoregions.
Then I research the habitats or sub-habitats that make up each ecoregion.
Then I research the list of species and subspecies of vertebrates native to the area. Then I trim out the species that are only visitors and not breeders there or for which the area is not the heart of their breeding range, but this is because my overall concept is zoogeographic.
Then I research each species and subspecies for range and habitat (to decide in what subarea of the ecoregion for display and the basic idea of the exhibit), size of the animal (for exhibit design, especially dimensions), mating/reproductive strategy (including territoriality) (whether to display singly, in pairs, in a group, etc.), diet (to avoid housing predators with prey, not just carnivores and herbivores, but also to avoid housing the many species that are nominally herbivores but are also eaters of eggs and nestlings with birds in multi-species exhibits) (and also to provide for live prey as part of the husbandry specifications when possible), relationship with water (to decided what's needed in the exhibit) and IUCN status. (This last occasionally means I'll decide a species is too rare to exhibit.) This can be the hard and exhausting part. I have often been surprised at how little of the information I want is available about many, many species. Sometimes you have to research one species under multiple common names and even multiple scientific names when there has been a change in the taxonomy within the last several decades or even century. Sometimes you have to rely on information about a related species and hope you're safe in doing so. Sometimes you have to use the SWAG method (Systematic Wild Ass Guess).
Then I consult the various standards for exhibit size and usually at least double them. There aren't standards available for all species, so I have developed some of my own, especially for birds, reptiles and amphibians.
Then I sort the species and subspecies into exhibits or groups of exhibits based on all this data, and hope inspiration strikes me for some ideas about shape and arrangement. I'll look at Zoolex to see if anything there helps with inspiration. Sometimes I just start drawing and see where it takes me. For the Palearctic Tundra, I started with the large mammal exhibits on a big, master drawing and sort of arranged them to mirror the geography of where the species/subspecies are found. Then I took all the bird and small mammal exhibits and cut out pieces of paper to scale for each of them and played around with different arrangements of them.
Except for the Galapagos, I gave up on trying to specify the plants. I just don't know enough about plants even properly to research them much less decide on which to include. My drawings are fairly limited in exhibit detail--they show short grass, long grass, sand, bare soil, gravel, rocks, deciduous trees, deciduous shrubs, evergreen shrubs, evergreen trees, logs, shallow freshwater, deep freshwater, shallow saltwater, deep saltwater, artificial ice and concrete (for moats mostly). It's fairly easy to decide which of these are needed/appropriate in a given exhibit.
Hope this helps.