Just forgot to say one thing - if you're going for a pure bred kitten - do your research very well. Look around the net, but also look at WHSmiths (or similar) and buy the
Your Cat magazine.
At the back there is a section that lists breeders.
Many new kitten buyers are bewildered and caught unaware by the mix of response when they phone to ask "do you have any kittens for sale"
Be prepared to be met with great caution and to answer a whole string of questions (to just about the colour of your underwear !
)
You might also find that you will have to go onto a waiting list if you want a particular breed of cat from a reputable breeder or put down a deposit to secure a kitten in advance.
Kittens should generally be very sociable and friendly. If you have kids or other pets, it does help (but is not that important) to get a breeder that raises it's kittens in the same manner. Most kittens do adjust quickly.
Last word of warning: there are many "rogue" breeders who are only in it for the money. So if going for a pure bred kitten - do your research
If you're going for a moggie, forget all that and just go for a kitten that looks happy, healthy and friendly
Oh by the way, I saw our local RSPCA advertise kittens in our local Petshop of all places. I would have though the RSPCA would never ever see the need to do so and if anything would have a waiting list. So keep a rescue centre in mind too.