With high blinds and a small stack, you should be more willing to play AJo.

Everyone's getting pressure from the blinds and will need to make moves instead of waiting for premium hands, which means AJo is more likely to be ahead of their ranges.

Important: Try to be the first person in the pot. If someone else enters the pot first, you have to decide whether AJo is good enough to stand up to them. Ideally you want them to be making that decision with whatever they're holding against you.

Definitely get Harrington on Hold'em (especially volume 2, which addresses late tournament play).