Heya.
Had a couple of people baffled as to how linkspun trades work...hope Nymph dont mind me using my attempt at explaining here as well. It aint my site - the owner Jdoughs is onhere, so please do correct me if any of my rants are wrong...
Basically - you add your main domain say
www.nymph.com .. but you dont wanna give people links from that, so as category you choose "hidden".
Then you add all the sites/urls you do want links on - say
www.nymph.com/links.html ,
www.nymphblog.com ,
www.iamblondetoday.com - in their appropriate categories.
So...I see
www.iamblondetoday.com and fancy a link on it, its a PR1 site and i have
www.blondesworldwide.com - so i request a link with a PR1 limit (means thats the highest pr backlink you can choose). You look at the request, and request a link from my site
www.nymphsarequitecool.com to
www.nymph.com - and hit accept...and we are then both asked to add the links.
so - you get a link to
www.nymph.com - i get one from another site to a fourth site. Nice A-B-C-D trade.
Equally, when you request - just in the opposite order of course.
You can request to and from any category, but most will deny your trade request if its blatantly irrelevant or unfair (say you ask for 5 pr6 links from mainstream sites in return for a pr0 pissing splog)
Does that help?