Re: What Would You Do With $3K To invest in Your Online Business?
@OP:
The one thing that's important for new business is stability. Work as hard as possible at the beginning to produce a stable income, even if it's not much. Then you can start to take more risks without so much risk, if you see what I mean 
As for exactly what to do with the money... working online is pretty cheap. There aren't really many overheads except hosting and domain names. Obviously you could spend the money on graphic designers, copywriters or informational products, but since you've only got $3k I'd say try and do as much as possible yourself.
So what would I do? I'd be very tempted to try buying an existing site to give myself something to start with. Improving something that is half assed is easier than starting from scratch, I reckon.
PROMOTE: Repeat commissions, huge evergreen niche, cheap and easy traffic:
Works great as a cross-sell for anything new-age, spiritual, quasi-religious, psychic/astrology or slightly wacky.