I recomend downloading
MAMP for your MySQL & PHP fucking around. It's worked out great for me. Super easy to install and play around with blogs offline. And it's nice & free.
Also install apps like mPlayer or the new intel VLC for your AVI's., Flip4Mac, Adium (my favor multi-chat client)... whatelse. Ah, thats enough for now...
Also check out Lynda.com. They have a few free video samples on OS X navigation.
if you have any questions I love helping out mac folks.
Hit me up on ICQ 264934933 :D