Spirit Shamans are kinda like druidic sorcerers. You have a limited spell list, but you can cast any spell on that list spontaneously. The cool twist is that you can change your spell list every day (the fluff is that your spirit guide 'retrieves' the spells for you). The downside is that you can only retrieve a max of 3 spells of any given level, and you have to specifically retrieve metamagic'd versions of spells (though your bonus feat doesn't count for this purpose).
Here's the exact text from Complete Divine:
[sblock] Like a sorcerer, a spirit shaman knows only a small number of spells. However, each day a spirit shaman may change the spells she knows. When a spirit shaman meditates to regain her daily allotment of spells (see below), she sends forth her spirit guide to bargain with the spirits and retrieve knowledge of the specific druid spells she will be able to use that day. She can cast any spell she has retrieved at any time, assuming she has not yet used up her spells per day for that spell level. For example, a 3rd-level spirit shaman can retrieve three 0-level, two 1st-level, and one 2nd-level druid spells. She can cast 0-level spells five times, 1st-level spells four times, and her 2nd-level spell two times in the course of the day. She might end up using the same 0-level spell five times, or one 0-level spell two times and another 0-level spell three times, or any combination that adds up to five uses of any of her 0-level spells.
If a spirit shaman knows any metamagic feats, she applies them to her spells when she retrieves her spells for the day. For example, a spirit shaman might choose to retrieve an empowered flame strike by using a 6th-level spell retrieved slot. Any time she uses flame strike during the ensuing day, she must use a 6th-level spell slot to cast it, and it is always empowered. A spirit shaman could use a 4th-level spell slot and a 6th-level spell slot to retrieve flame strike and empowered flame strike if she wanted to have both spells available to her in a day. A spirit shaman cannot choose to alter her spells with metamagic feats on the fly, as other spontaneous casters do. Spirit shamans using metamagic feats do not have an increased casting time as sorcerers do.[/sblock]
As a first level Spirit Shaman, you can retrieve 3 0th level spells and 1 1st level spell, chosen from the Druid spell list from any WotC book. You can change the spells you retrieve every day.