Normally the textbook is sufficient for unit 1 and 2, I think going beyond isn't required to do well in a unit 2 test 
Yeah, sticking to the textbook and just googling the topics listed should be good. You'd have to consider what you've been taught in class and what the test will cover (e.g. will it cover the stoich stuff as well?)
There's worksheets, explanations etc. here (for an American course though):
http://misterguch.brinkster.net/helpdesk2.htmlChemguide quickly goes beyond what we're learning:
http://www.chemguide.co.uk/physical/acidbaseeqia/theories.htmlIf you go to a state school, you should be on the ultranet. Go to the "Collaborative Learning" and search for the group called "Year 11 Chemistry" and the space owner is "Catherine Blayney" - Join it and go to Unit 2 (you can't go through the tab at the top - it doesn't work, you have to scroll down and click Unit 2), there's lots of PowerPoints and worksheets there.
KhanAcademy has some chemistry videos.
I've got a few Unit 1/2 trial exams, they should have some Acids and Bases questions in there. PM me if you want them.