Also using Clearbooks myself. (Free version)

If in a broad sense, if you are running quite a straightforwards business its all quite simple.  I can add all the info that I already add to my spreadsheet everyday. Takes moments.

As in, buy stuff, sell it, buy in packing stuff,  pay for postage, bit of mileage. That sort of thing.

There's a long thread on the Business Seller Board with good advice on how to use it.