Hi John,
I’m a beginner too, just started a few weeks ago. In the first thread I started, harper gave me some tips that have helped quite a bit. You can find that thread here. Matt is also a beginner who’s progressed quite rapidly, and has been keeping a journal of his progress with many, many tips for us beginners. You can find his journal here. I’m also keeping a journal of sorts in a blog that I started, though it’s more for entertainment of family and friends than for helping other beginners; if you’re interested, the URL is in my signature.
I’m also having the same trouble you’re having with stopping at a change in terrain (pavement-to-grass). For myself, I’m fairly certain that that trouble will decrease substantially (hopefully altogether!) once I feel like I’m in control at all times on the pavement, so I’m not worrying about it too much. I’ve moved to a park for my practice area, and I’ve got nice, long paths to stay on the pavement (when I don’t UPD onto the grass); you might try to find some larger/longer paved areas until you feel comfortable. Or maybe you need to try starting on the grass instead; I don’t think that would work for me, but everyone’s different.
In this thread, jsm posted this link, which has a video of idling. Hope that helps with the idle question; as for me, I’m a long way from idling!
Best of luck, and keep us posted!
Rich