Back in 1999-2000 I had that problem, but with a much larger scale operation. The only electronic devices we had in the construction trailer was a desktop calculator, and a semi-broken fax machine.
Anyways, I took it upon myself to get something software based going, including build-outs, change orders, warranty schedules, costing, etc.
Settled on ACT! (then by Symantec), and it was one of the best and luckiest decisions I ever made.
But it's not like falling off a chair. You have to first figure out what you really want to do/can do, and then commit to it.
And then comes the learning curve on the software. And I don't care what brand/edition you eventually settle on, it can be overwhelming at first.
Virtually EVERYTHING construction industry centered is going to be overkill for a 1 man operation, IMO, and pricey.
Get something cheap or free and play with it, to see where you need to be, or if you even will stick with it over the long term.