Hi Neil
The most important point with livebait rigs for perch is to avoid resistance. For this reason I prefer floats whenever possible, and I've had most success with wagglers. This is contrary to the books, but the sunken line with a waggler slows the bait down and also keeps it near the groundbait. In fact, if you fish overdepth the bait often stays put - except for when it's taken by a hungry perch!
Running ledgers and running paternosters also work well, although I find that the perch quickly wise up to the way a paternosted bait behaves. I prefer to start with a brightly coloured sunken float, and in murky water often use my "rattle rig" as Dave Will described.
I've written several articles for another online mag, but in fairness to Graham I'd suggest you e-mail me for the url, that is if you haven't already guessed what it is!
As to hooks I now use Ashima Super Maggots, which I've found far better than the Aberdeens I used to recommend. In particular they have the smallest barbs I've ever seen. Unfortunately they've now been discontinued. If you pop into me next time you're over this way I'll give you a packet. If not e-mail me your snail mail address and I'll post you some.