I use Quickbooks for my accounting software and FotoQuote to estimate pricing. I’ve been using Quickbooks since around 1999 and am very happy with it. Great for invoicing, makes things very easy at tax time and gives me good reports on my receivables and expenses. I don’t like their budgeting, but overall I love the program. PhotoQuote is a good start for negotiating a price for a stock sale, but it’s a little weak for assignment work, but a good resource overall. I’ve used it since around 2003.
I tried Photobyte and didn’t like it. Quicken is a good program for budgeting, but it’s geared mainly for household finances. Quickbooks is much better for my needs.
Check out the Editorial Photographer’s website. They have alot of resources that might give you a better idea of what’s out there.