Edward, I'd check out Intuit's QuickBooks software for your accounting purposes. From my experience while working for an electrical estimating software company, 70% of our customers use it and have found success with it.
Regarding estimating software... there are several software packages out there that are geared for meeting the need of someone wanting to get started with computerized estimating. I work for Vision InfoSoft and we make the Electrical Bid Manager software line. Several of our competitors make comparable products that you may want to look into also.
Also... many estimators have success using Microsoft's Excel spreadsheets or any other spreadsheet software. You may not need the advanced features of a dedicated software product.
Hopefully this post will get someone else's attention so you can get more feedback. I'd suggest doing a little research on your own with internet search engines. Try doing a search in www.Google.com
for "electrical estimating" or "electrical estimating software". These keyword combinations will provide you with several good software packages to research.