When I got my two, we had one of each. Hestia made herself right at home, but Bacardi hid under a cupboard for several days. We were really worried about him at the time, but we now know hes just a bit of a wimp! When my cats first went to my parents as we were laying a wooden floor, Bacardi actually hid in the most ridiculously small gap behind the sofa. And he is not a small cat. My mum took ages to find him as she never thought he would fit!
The advice I read was to keep the cat in one room at first, and not to bother it too much. Make sure it has food, water, litter and a hidey hole (a cardboard box with a blanket in would be good, somewhere it can hide in/under). Best you choose this place yourself, and block up any other small places it might get into. Also, some toys are good - a cat has to be comfortable to play.
With Hestia, I used to sit in the kitchen, where were kept them the first few nights, on the floor so she could climb on my lap, which she did. Bacardi, we just used to stroke a little if he looked like he would let us. Try not to force attention on them, as they are probably pretty scared.
Gradually, we let them in more rooms. First the living room during the day, then overnight, then upstairs during the day, then overnight, etc.
Both cats are now totally comfortable in the house. They climb everywhere. Bacardi is a complete cuddle cat and likes to come and sit between me and the OH in bed and purr like a tractor (thats how he wakes us up to get the fuss made of him).
From my limited experience (and the Kittens for Dummies book!) - don't overwhelm them, let them find their own way out and about. From my own experience with Bacardi - don't panic if they hide somewhere small and dark for several days!
Hope that all helps.
