I was using MOYB until they went out of business and QuickBooks tried to take over but was too confusing.
If you are looking for a simple accounting solution for a small business (that isn't Quickbooks), I recommend Xero. It calls itself the "beautiful accounting software," and looking at its interface doesn't make me question it. The software offers a free trial if you're interested.
Another accounting solution (which has actually won awards for its ease of use) is Intacct. This solution also has a free trial. Please do check them out. I'm certain you would have a positive experience with either of them.
Xero and Intacct are decent products, as Miranda suggests. But if you haven't already committed to one of those (or something else), there's a new player about to hit the market, well worth looking into: Billy's Billing (http://billysbilling.com).
The big plus with this app is that - unlike QuickBooks and most others - it doesn't assume the user is an accountant. In fact, it assumes you're NOT. No special accounting jargon, no strict and complicated procedures only a CPA could love. Simple and straightforward. (It's even beautiful. I'd say more beautiful than Xero - but I'm biased, of course!)
If that sounds like a good fit, check out their website. They've got a free trial offer so you can give it a spin before you commit.