The first thing to do, even before buying a wisteria of any description, is to fix a strong support, such as a rigid trellis panel, to the wall, preferably on battens so that there's a gap behind to enable the wisteria to twine properly.
As for choice of plant, the usual one in Britain has been Wisteria sinensis, which has the full flowers you see everywhere. Always buy a grafted variety, or one grown from cuttings, from a reputable supplier, and don't choose one grown from seed - seed grown ones take years to flower and the flowering is often poor.
There are a couple of other varieties commonly available now - an American one, Wisteria frutescens varieties, and a Japanese one, Wisteria floribunda. In all, there are 10 varieties of Wisteria, not all of which are available here. The American varieties flower at a younger age, but the flower form is different, having a long part at the bottom without full flowers on it.
Learn to train and prune it properly - pruning increases flower production. The RHS has a page on Wisteria and pruning, and also a video you can watch to see how to do it.

That's brilliant, Bamboo! Thanks. Going to the RHS page straightaway. :)

If you have trouble finding it, type wisteria into Google - should come up on the first page about 4 entries down...

Go for it, Naturelover - we have a couple and they are brilliant and smell so gorgeous.
May I second Bamboo's advice about the REALLY robust trellis? Ours covered the entire top 3 storeys of the East wall of our house until heavy snow this year weighed so much it tore large chunks of it away from the wall, and we had to cut out a lot of it where it had been damaged. At least the cats can't climb up to the attic windows or the roof and get trapped now!
Don't be afraid of pruning it too hard, either. It WILL recover!

Thanks for sharing your experience, Gattina. Will get a really sturdy trellis. :)

Hi Naturelover, an alternative to trellis would be to 'wire' the wall and tie the Wisteria to the wire as it grows. This would be cheaper and allow you to go as high and wide and wherever you like.
I inherited my plant when I moved to this house and there were bits of wooden trellis twisted amongst it - none of it still attached to the wall at all. The Wisteria stood against the house self-supported like a tree. I had to give it a severe prune to get it into shape the first Winter and took the opportunity to drill and plug the wall, screwing in 'eyed screws' and running 'Gripple System' plastic wire through the eyes. (Check this link http://www.growsonyou.com/photo/slideshow/123133-gripple-system-photo1/member/muddywalters)

Mark

Oh, Muddywalter, this is what was our undoing! We had ours wired to the wall, and that's when the weight of snow pulled it away - the wire just wasn't strong enough, and it had been fixed REALLY securely into the stone. We thought! Maybe there isn't a truly safe system of any sort!
Actually, you do have a very valid point - wisterias grow very large very quickly (or they can do) and will twist round and then destroy any but the most robust of trelliswork as the trunks get big and bursts it.