Hello all, long time reader, 4th time poster.

I just picked up the a300, 18-70 and 75-300 lenses. I am impressed after day 1. Anyhow, I am a former point and shoot guy and was wondering if anyone knows of literature, tips, etc to get the most out of my a300. I'm afraid that I'll just leave it on "auto" instead of moving into more advanced photography. My previous cameras had scenes, but never allowed for optimization of the settings like this camera is capable of.

What are the critical accessories (filters, flashes, etc) that I should consider as the budget allows?

Looking forward to learning what this camera can do for me.