[Craig Larson]"1. I have a 2011 MBP with Thunderbolt and 8gb of ram. I'm assuming this will be enough horsepower to run AE?"
AE's performance scales with hardware. You can run AE on a MBP with 8 GB of RAM, but it'll render a lot faster on a 6-core Mac Pro with 24 GB, and faster still on a 12-core with 48 GB.
[Craig Larson]"2. I've seen the software priced at around $500. Is there better pricing anywhere? Also, would it be beneficial to buy an older version off eBay and then purchase an upgrade?"
Retail for AE alone is $999.
Adobe's SWITCH campaign is back on, getting you the entire Production Premium suite for less than the cost of AE alone.
Adobe Creative Cloud subscription licensing [link] will be available in the first half of this year, getting you the entire Creative Suite Master Collection for $50/mo. Until the new pricing plan kicks in, you can subscribe to AE alone [link] for $75/mo (month by month) or $50/mo (if you pay a whole year).
[Craig Larson]"3. What's the best book/training/site for AE?"
I especially recommend the Video Copilot "Basic Training" series that Todd links to.
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