Faster Grinding: Priest (World of Warcraft guild)

For grinding up a shadow priest (if you're going to go holy from the start don't bother grinding, run instances for your exp) stick to mobs about your lvl until you're around 40'ish then you can move up. You can kill mobs higher than you before that of course, but the xp/hour will be less. Green mobs are your friend.

Before you hit shadow form and have improved VE I would pull with mindblast, drpo a SW:P on the mob, shield, flay once or twice and then wand the rest of the way. With shadowform and imp VE I drop the PW:S (Power Word Shield) as it's incredibly mana ineffeciant and VE will top me off almost all the way during the course of every fight.

IMHO First Aid should be learned by every class and I have my first aid right up there as well, but I don't waste bandages during grinding sessions. Generally I'll sit down and eat some food when I have to drink every so often. Many of the higher level foods will give you nifty abilities such as increasing stam and spirit for 15 minutes if you spend 10 seconds eating it. I also love to have mages on the friends list that will drop me a stack of 80 conjured water as it saves on drink costs during long (10 hour+) grinding sessions.

When you're starting out wanding is a must and even at a higher level wanding is a must. When wanding you also get out of FSR (Five Second Rule) so you can begin regenerating mana quicker. When spirit tap kicks in it's almost as good as drinking. In addition your first wand should always be Lesser Magic Wand:

http://thottbot.com/?i=1325

This is made by a low level enchanter, you can use it at lvl 5, and it pumps out 11.3 DPS (can be had for very cheap as well).

I ended up with Cookies Stiring Rod next ( http://thottbot.com/?i=6502 ) which is from the DeadMine but the Greater Magic Wand (again from an enchanter) is another wonderful wand: http://thottbot.com/?i=1318

Greater Magic Wand: lvl 13 and 17.5 damage per second
Cookies Stiring Rod: lvl 17 and 22.3 damage per second

After those wands there's not much you can get on the cheap from enchanters for wands, you'll be looking at green drops.

For pure grinding I like a good mix of int/spi but don't get too hung up in stats. Once you hit lvl 40 and get Shadowform everything becomes a lot more fun.