This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
The easiet thing to do if you're looking for something specific is to go to the SCJP TipLine and do a Search for whatever you're looking for (the Search is in the top right corner). Typing in "Garbage Collection" got me this link:
You may also want to check out the JavaRanch Journal as I've been putting my SCJP TipLine posts there lately, rather than in my blog. This article, specifically, has a bit to do with garbage collection: