[OblivionMage]

It seems to load all of the links on loading the page.

If you go to, say:
http://www.wowguideonline.com/inscription.html
(This is just an example)
It seems to load the item tooltips once you hover over the items, rather then do it all in advance, although I suppose this could be achived with adding the item id / link.

just an idea, but could you add something like [spell] tags so it does the same thing with spells as it does with items?

WoWHead doesn't have spell tags, but if you link the text to the URL of the spell, it should come up as a tooltip (for example: http://guidewiki.com/forums/world-wa...ide-wotlk.html). If you want it to look just like an item link, just add font/color tags inside of the URL tag.