kjlltd - That's very good advice. When you have a business, you should focus on what you are good at and hire out the rest.
That said, there are some things that no matter how hard you try, you can't farm out to anybody else (believe me I've tried!). Time tracking is on of those things. Unless you have someone following you around 24/7, as a consultant you have to be the one keeping track. For me, (and probably others) this is extremely difficult! When it comes time to invoice, in the past I would scour emails, files, post-it notes for any information about how much time I spent and then just end up guesstimating my hours anyway, shaving off a few here and there.
What works for me now is a piece of software called Standard Time (stdtime.com). It integrates with Quickbooks and is more robust than their Timer application. It's not perfect (it's based on MS Access), but it works for me. I am able to set up multiple projects for each client. It's simple to use the timer. You just right-click on the timer icon in the system tray and select the project you are working on. Right-click again to turn it off. That's about as much interaction I can handle when I'm tracking time on a project! (note: they also have a handheld version of their software for PDAs)
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