Anyone still using SQL Ledger should be aware that new versions are no longer released under the GPL. When I wrote the book, and for several years afterward, SQL Ledger was the only game in town, and it's been the only viable open source financial web application for quite some time.
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We've been making websites since the start of the web, and know what makes them work -- as well as not work. Take what we have learned to make your site better!