See some of the answers in topic below 'thinking of getting some pigs'.
If you're only going to do one batch of weaners to see how you get on, why not make your own pig house theres lots of suggestions in various books and on various websites, but remember it will need to robust, windproof and weather proof to survive the coming winter!
If you want to buy an ark most ag merchants sell them but beware of paying up front on internet sites there have been a number of bad experiences recently, one of the others will no doubt be along with a reliable recommendation (can't help as we make our own, OH is a builder!)
pig feed agian most ag merchants sell pig feed as for sow/weaner nuts/cubes 16% protein probably the most well known brand in your area.
HTH
mandy