I would probably say an Enhancement Shaman is better for solo PvEing leveling where else a Restoration Shaman is a much better choice if you are into instance grouping.

An Elemental Shaman is not bad in PvE but as some had stated, it have quite a lot of downtimes due to the need for mana. But it is one of the better choice if you are into PvPing since Elemental really puts the P into pain.

And for your leveling gear, you should try getting Str for AP, Sta for HP and Agi for critical chance. a little of Int sprinkle into the gears since the Mana would only be used in the weapon buffs as well as some heals.

You would still be needed to buy some water and/or food but not as much as a full Elemental Shaman.

Hope all that rabbling helps.