The Highlander format is mad easy: The only rule is that every card in your deck must be a one-of. The exception is technically basic land, but most people like to limit that to one as well.
Although I'm not certain, I'm guessing the artist format is just that you have to make a deck using cards from the same artist, probably with the exception again of basic lands.
As for resources on decklists, etcetera, for Highlander you can use the search option for this Forum. Also, back in Sept. or Oct., a Highlander tourney was held in Endicott. Just Search the Tournament Forum for that.
As far as artists format, I don't know that there's any threads here, but it's worth a search. Also, on
www.magicthegathering.com, you should be able to find decklists for the format used at the 2004 Invitational. Check Magic Arcana in particular. I believe the decks there had to Online Extended (Invansion+) legal, though, so I'm sure the aren't optimal.
EDIT: I decided I had nothing better to do. Here are some links:
bebe's ReportKowal's Highlander Message Boardkasuras's Reportkl0wn's Primer (A Must Read!) A Starcity Article on HighlanderThere's plenty more, and I'm plenty lazy.
