Reddit reviews The Scottish Nation: 1700-2007

For a good general overview of Scotland's history you can't go far wrong with Michael Lynch's Scotland: A New History and my dad says that Neil Oliver's book A History of Scotland is good as well. I've not read it myself, but given that it's aimed at a general audience instead of historians it's possibly more readable than Lynch's book.

For modern Scottish history Tam Devine's book The Scottish Nation: 1700-2007 is a pretty good start. I find him quite readable, but it's more of a social history than a dates and facts history. I've taken against him a bit lately as he keeps sticking his oar in whenever there's a social issue on the go (Rangers going into administration was the latest), but I can't fault him for his knowledge and research work. I've a lot of respect for him as a historian.

The articles on Scottish History on Wikipedia tend to be quite well written, researched and sourced so you might find more specific books and information from their footnotes.