My favorite for (most) vocals is the AKG Solidtube; I've seen them for as little as $699. For acoustic guitar, Neumann TLM103, but that's a bit pricey at about $1000. But if you want ONE mic suitable for vocals AND guitar, then I've always liked the CAD mics. This one is great choice:
http://www.cadmics.com/e300_2.htm