Ask HN: How to keep organized and on target

I just left the startup I was working for, and for the foreseeable future I will be doing some contracting to pay the bills and working on my own software.

I will be working from home for both, and in order to handle all of this I would like to become more organized and methodical than I usually am (and is usually required).

So specifically, any suggestions on tools:

-dealing with everything about the company, from tax receipts, business cards to keeping to a dev schedule

-handling everything for the contracting, from tracking the number of billable hours to details from a phone call about a project

I have a reasonable idea of how I can handle this - but this community always surprises me with really helpful information about these type of things.

Any other advice will also be helpful, this is day 1 so the list of things I need to do is pages long!